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Xin Y, Xing CK, Zhou HD, Liu J. Defects in Pyrochlore Dy2Ti2O7 Thin Film. Microsc Microanal 2023; 29:1665-1666. [PMID: 37613911 DOI: 10.1093/micmic/ozad067.857] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/25/2023]
Affiliation(s)
- Yan Xin
- National High magnetic Field Laboratory, Florida State University, Tallahassee, Florida, USA
| | - C K Xing
- Department of Physics and Astronomy, University of Tennessee, Knoxville, Tennessee, USA
| | - H D Zhou
- Department of Physics and Astronomy, University of Tennessee, Knoxville, Tennessee, USA
| | - J Liu
- Department of Physics and Astronomy, University of Tennessee, Knoxville, Tennessee, USA
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2
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Chen J, Wei JQ, Hong MN, Zhang Z, Zhou HD, Lu YY, Zhang J, Guo YT, Chen X, Wang JG, Gao PJ, Li XD. Mitogen-Activated Protein Kinases Mediate Adventitial Fibroblast Activation and Neointima Formation via GATA4/Cyclin D1 Axis. Cardiovasc Drugs Ther 2023:10.1007/s10557-023-07428-1. [PMID: 36652042 DOI: 10.1007/s10557-023-07428-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 01/09/2023] [Indexed: 01/19/2023]
Abstract
PURPOSE Activation of mitogen-activated protein kinases (MAPKs) by pathological stimuli participates in cardiovascular diseases. Dysfunction of adventitial fibroblast has emerged as a critical regulator in vascular remodeling, while the potential mechanism remains unclear. In this study, we sought to determine the effect of different activation of MAPKs in adventitial fibroblast contributing to neointima formation. METHODS Balloon injury procedure was performed in male 12-week-old Sprague-Dawley rats. After injury, MAPK inhibitors were applied to the adventitia of injured arteries to suppress MAPK activation. Adventitial fibroblasts were stimulated by platelet-derived growth factor-BB (PDGF-BB) with or without MAPK inhibitors. RNA sequencing was performed to investigate the change of pathway and cell function. Wound healing, transwell assay, and flow cytometry were used to analyze adventitial fibroblast function. RESULTS Phosphorylation of p38, c-Jun N-terminal kinase (JNK), and extracellular regulated kinases 1/2 (ERK1/2) was increased in injured arteries after balloon injury. In primary culture of adventitial fibroblasts, PDGF-BB increased phosphorylation of p38, JNK, ERK1/2, and extracellular regulated kinase 5 (ERK5) in a short time, which was normalized by their inhibitors respectively. Compared with the injury group, perivascular administration of four MAPK inhibitors significantly attenuated neointima formation by quantitative analysis of neointimal area, intima to media (I/M) ratio, and lumen area. RNA sequencing of adventitial fibroblasts treated with PDGF-BB with or without four inhibitors demonstrated differentially expressed genes involved in multiple biological processes, including cell adhesion, proliferation, migration, and inflammatory response. Wound healing and transwell assays showed that four inhibitors suppressed PDGF-BB-induced adventitial fibroblast migration. Cell cycle analysis by flow cytometry demonstrated that JNK, ERK1/2, and ERK5 but not p38 inhibitor blocked PDGF-BB-induced G1 phase release associated with decrease expression of cell cycle protein Cyclin D1 and transcription factor GATA4. Moreover, four inhibitors decreased macrophage infiltration into adventitia and monocyte chemoattractant protein-1 (MCP-1) expression. CONCLUSION These results suggest that MAPKs differentially regulate activation of adventitial fibroblast through GATA4/Cyclin D1 axis that participates in neointima formation.
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Affiliation(s)
- Jing Chen
- Department of Cardiovascular Medicine, Department of Hypertension, Ruijin Hospital and State Key Laboratory of Medical Genomics, Shanghai Key Laboratory of Hypertension, Shanghai Institute of Hypertension, Shanghai Jiao Tong University School of Medicine, 197 Ruijin 2nd Road, 200025, Shanghai, China
| | - Jin-Qiu Wei
- Department of Cardiovascular Medicine, Department of Hypertension, Ruijin Hospital and State Key Laboratory of Medical Genomics, Shanghai Key Laboratory of Hypertension, Shanghai Institute of Hypertension, Shanghai Jiao Tong University School of Medicine, 197 Ruijin 2nd Road, 200025, Shanghai, China
| | - Mo-Na Hong
- Department of Cardiovascular Medicine, Department of Hypertension, Ruijin Hospital and State Key Laboratory of Medical Genomics, Shanghai Key Laboratory of Hypertension, Shanghai Institute of Hypertension, Shanghai Jiao Tong University School of Medicine, 197 Ruijin 2nd Road, 200025, Shanghai, China
| | - Zhong Zhang
- Department of Cardiovascular Medicine, Department of Hypertension, Ruijin Hospital and State Key Laboratory of Medical Genomics, Shanghai Key Laboratory of Hypertension, Shanghai Institute of Hypertension, Shanghai Jiao Tong University School of Medicine, 197 Ruijin 2nd Road, 200025, Shanghai, China
| | - Han-Dan Zhou
- Department of Cardiovascular Medicine, Department of Hypertension, Ruijin Hospital and State Key Laboratory of Medical Genomics, Shanghai Key Laboratory of Hypertension, Shanghai Institute of Hypertension, Shanghai Jiao Tong University School of Medicine, 197 Ruijin 2nd Road, 200025, Shanghai, China
| | - Yuan-Yuan Lu
- Department of Cardiovascular Medicine, Department of Hypertension, Ruijin Hospital and State Key Laboratory of Medical Genomics, Shanghai Key Laboratory of Hypertension, Shanghai Institute of Hypertension, Shanghai Jiao Tong University School of Medicine, 197 Ruijin 2nd Road, 200025, Shanghai, China
| | - Jia Zhang
- Department of Cardiovascular Medicine, Department of Hypertension, Ruijin Hospital and State Key Laboratory of Medical Genomics, Shanghai Key Laboratory of Hypertension, Shanghai Institute of Hypertension, Shanghai Jiao Tong University School of Medicine, 197 Ruijin 2nd Road, 200025, Shanghai, China
| | - Yue-Tong Guo
- Department of Cardiovascular Medicine, Department of Hypertension, Ruijin Hospital and State Key Laboratory of Medical Genomics, Shanghai Key Laboratory of Hypertension, Shanghai Institute of Hypertension, Shanghai Jiao Tong University School of Medicine, 197 Ruijin 2nd Road, 200025, Shanghai, China
| | - Xin Chen
- Department of Cardiovascular Medicine, Department of Hypertension, Ruijin Hospital and State Key Laboratory of Medical Genomics, Shanghai Key Laboratory of Hypertension, Shanghai Institute of Hypertension, Shanghai Jiao Tong University School of Medicine, 197 Ruijin 2nd Road, 200025, Shanghai, China
| | - Ji-Guang Wang
- Department of Cardiovascular Medicine, Department of Hypertension, Ruijin Hospital and State Key Laboratory of Medical Genomics, Shanghai Key Laboratory of Hypertension, Shanghai Institute of Hypertension, Shanghai Jiao Tong University School of Medicine, 197 Ruijin 2nd Road, 200025, Shanghai, China
| | - Ping-Jin Gao
- Department of Cardiovascular Medicine, Department of Hypertension, Ruijin Hospital and State Key Laboratory of Medical Genomics, Shanghai Key Laboratory of Hypertension, Shanghai Institute of Hypertension, Shanghai Jiao Tong University School of Medicine, 197 Ruijin 2nd Road, 200025, Shanghai, China
| | - Xiao-Dong Li
- Department of Cardiovascular Medicine, Department of Hypertension, Ruijin Hospital and State Key Laboratory of Medical Genomics, Shanghai Key Laboratory of Hypertension, Shanghai Institute of Hypertension, Shanghai Jiao Tong University School of Medicine, 197 Ruijin 2nd Road, 200025, Shanghai, China.
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Huang Q, Rawl R, Xie WW, Chou ES, Zapf VS, Ding XX, Mauws C, Wiebe CR, Feng EX, Cao HB, Tian W, Ma J, Qiu Y, Butch N, Zhou HD. Non-magnetic ion site disorder effects on the quantum magnetism of a spin-1/2 equilateral triangular lattice antiferromagnet. J Phys Condens Matter 2022; 34:205401. [PMID: 35189602 DOI: 10.1088/1361-648x/ac5703] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/06/2021] [Accepted: 02/21/2022] [Indexed: 06/14/2023]
Abstract
With the motivation to study how non-magnetic ion site disorder affects the quantum magnetism of Ba3CoSb2O9, a spin-1/2 equilateral triangular lattice antiferromagnet, we performed DC and AC susceptibility, specific heat, elastic and inelastic neutron scattering measurements on single crystalline samples of Ba2.87Sr0.13CoSb2O9with Sr doping on non-magnetic Ba2+ion sites. The results show that Ba2.87Sr0.13CoSb2O9exhibits (i) a two-step magnetic transition at 2.7 K and 3.3 K, respectively; (ii) a possible canted 120 degree spin structure at zero field with reduced ordered moment as 1.24μB/Co; (iii) a series of spin state transitions for bothH∥ab-plane andH∥c-axis. ForH∥ab-plane, the magnetization plateau feature related to the up-up-down phase is significantly suppressed; (iv) an inelastic neutron scattering spectrum with only one gapped mode at zero field, which splits to one gapless and one gapped mode at 9 T. All these features are distinctly different from those observed for the parent compound Ba3CoSb2O9, which demonstrates that the non-magnetic ion site disorder (the Sr doping) plays a complex role on the magnetic properties beyond the conventionally expected randomization of the exchange interactions. We propose the additional effects including the enhancement of quantum spin fluctuations and introduction of a possible spatial anisotropy through the local structural distortions.
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Affiliation(s)
- Q Huang
- Department of Physics and Astronomy, University of Tennessee, Knoxville, TN 37996, United States of America
| | - R Rawl
- Department of Physics and Astronomy, University of Tennessee, Knoxville, TN 37996, United States of America
| | - W W Xie
- Department of Chemistry and Chemical Biology, Rutgers University, Piscataway, NJ 08854, United States of America
| | - E S Chou
- National High Magnetic Field Laboratory, Florida State University, Tallahassee, FL 32310, United States of America
| | - V S Zapf
- National High Magnetic Field Laboratory, Los Alamos National Laboratory, Los Alamos, NM 87545, United States of America
| | - X X Ding
- National High Magnetic Field Laboratory, Los Alamos National Laboratory, Los Alamos, NM 87545, United States of America
| | - C Mauws
- Department of Chemistry, University of Manitoba, Winnipeg, Manitoba R3T 2N2, Canada
| | - C R Wiebe
- Department of Chemistry, University of Manitoba, Winnipeg, Manitoba R3T 2N2, Canada
- Department of Chemistry, University of Winnipeg, Winnipeg, Manitoba R3B 2E9, Canada
- Department of Physics and Astronomy, McMaster University, Hamilton, Ontario L8S 4M1, Canada
| | - E X Feng
- Neutron Scattering Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, United States of America
| | - H B Cao
- Neutron Scattering Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, United States of America
| | - W Tian
- Neutron Scattering Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, United States of America
| | - J Ma
- Laboratory of Artificial Structures and Quantum Control, School of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240, People's Republic of China
- Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, 110016 Shenyang, People's Republic of China
| | - Y Qiu
- NIST Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, MD 20899, United States of America
| | - N Butch
- NIST Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, MD 20899, United States of America
| | - H D Zhou
- Department of Physics and Astronomy, University of Tennessee, Knoxville, TN 37996, United States of America
- National High Magnetic Field Laboratory, Florida State University, Tallahassee, FL 32310, United States of America
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4
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Rao X, Hussain G, Huang Q, Chu WJ, Li N, Zhao X, Dun Z, Choi ES, Asaba T, Chen L, Li L, Yue XY, Wang NN, Cheng JG, Gao YH, Shen Y, Zhao J, Chen G, Zhou HD, Sun XF. Survival of itinerant excitations and quantum spin state transitions in YbMgGaO 4 with chemical disorder. Nat Commun 2021; 12:4949. [PMID: 34400621 PMCID: PMC8367942 DOI: 10.1038/s41467-021-25247-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2020] [Accepted: 07/01/2021] [Indexed: 11/16/2022] Open
Abstract
A recent focus of quantum spin liquid (QSL) studies is how disorder/randomness in a QSL candidate affects its true magnetic ground state. The ultimate question is whether the QSL survives disorder or the disorder leads to a “spin-liquid-like” state, such as the proposed random-singlet (RS) state. Since disorder is a standard feature of most QSL candidates, this question represents a major challenge for QSL candidates. YbMgGaO4, a triangular lattice antiferromagnet with effective spin-1/2 Yb3+ions, is an ideal system to address this question, since it shows no long-range magnetic ordering with Mg/Ga site disorder. Despite the intensive study, it remains unresolved as to whether YbMgGaO4 is a QSL or in the RS state. Here, through ultralow-temperature thermal conductivity and magnetic torque measurements, plus specific heat and DC magnetization data, we observed a residual κ0/T term and series of quantum spin state transitions in the zero temperature limit for YbMgGaO4. These observations strongly suggest that a QSL state with itinerant excitations and quantum spin fluctuations survives disorder in YbMgGaO4. It remains an open question as to whether the quantum spin liquid state survives material disorder, or is replaced by some spin-liquid like state. Here, Rao et al succeed in resolving a resolving a κ0/T residual in the thermal conductivity of YbMgGaO4 strongly suggesting the survival of the quantum spin liquid state.
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Affiliation(s)
- X Rao
- Hefei National Laboratory for Physical Sciences at Microscale, Department of Physics, and Key Laboratory of Strongly-Coupled Quantum Matter Physics (CAS), University of Science and Technology of China, Hefei, Anhui, People's Republic of China
| | - G Hussain
- Hefei National Laboratory for Physical Sciences at Microscale, Department of Physics, and Key Laboratory of Strongly-Coupled Quantum Matter Physics (CAS), University of Science and Technology of China, Hefei, Anhui, People's Republic of China
| | - Q Huang
- Department of Physics and Astronomy, University of Tennessee, Knoxville, TN, USA
| | - W J Chu
- Hefei National Laboratory for Physical Sciences at Microscale, Department of Physics, and Key Laboratory of Strongly-Coupled Quantum Matter Physics (CAS), University of Science and Technology of China, Hefei, Anhui, People's Republic of China
| | - N Li
- Hefei National Laboratory for Physical Sciences at Microscale, Department of Physics, and Key Laboratory of Strongly-Coupled Quantum Matter Physics (CAS), University of Science and Technology of China, Hefei, Anhui, People's Republic of China
| | - X Zhao
- School of Physical Sciences, University of Science and Technology of China, Hefei, Anhui, People's Republic of China
| | - Z Dun
- Department of Physics and Astronomy, University of Tennessee, Knoxville, TN, USA
| | - E S Choi
- National High Magnetic Field Laboratory, Florida State University, Tallahassee, FL, USA
| | - T Asaba
- Department of Physics, University of Michigan, Ann Arbor, MI, USA
| | - L Chen
- Department of Physics, University of Michigan, Ann Arbor, MI, USA
| | - L Li
- Department of Physics, University of Michigan, Ann Arbor, MI, USA
| | - X Y Yue
- Institute of Physical Science and Information Technology, Anhui University, Hefei, Anhui, People's Republic of China
| | - N N Wang
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing, People's Republic of China
| | - J-G Cheng
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing, People's Republic of China
| | - Y H Gao
- State Key Laboratory of Surface Physics and Department of Physics, Fudan University, Shanghai, People's Republic of China
| | - Y Shen
- State Key Laboratory of Surface Physics and Department of Physics, Fudan University, Shanghai, People's Republic of China
| | - J Zhao
- State Key Laboratory of Surface Physics and Department of Physics, Fudan University, Shanghai, People's Republic of China
| | - G Chen
- State Key Laboratory of Surface Physics and Department of Physics, Fudan University, Shanghai, People's Republic of China. .,Department of Physics and HKU-UCAS Joint Institute for Theoretical and Computational Physics at Hong Kong, The University of Hong Kong, Hong Kong, China.
| | - H D Zhou
- Department of Physics and Astronomy, University of Tennessee, Knoxville, TN, USA.
| | - X F Sun
- Hefei National Laboratory for Physical Sciences at Microscale, Department of Physics, and Key Laboratory of Strongly-Coupled Quantum Matter Physics (CAS), University of Science and Technology of China, Hefei, Anhui, People's Republic of China. .,Institute of Physical Science and Information Technology, Anhui University, Hefei, Anhui, People's Republic of China.
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5
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Mauws C, Hiebert N, Rutherford ML, Zhou HD, Huang Q, Stone MB, Butch NP, Su Y, Choi ES, Yamani Z, Wiebe CR. Magnetic ordering in the Ising antiferromagnetic pyrochlore Nd 2ScNbO 7. J Phys Condens Matter 2021; 33:245802. [PMID: 33827056 DOI: 10.1088/1361-648x/abf594] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/22/2021] [Accepted: 04/07/2021] [Indexed: 06/12/2023]
Abstract
The question of structural disorder and its effects on magnetism is relevant to a number of spin liquid candidate materials. Although commonly thought of as a route to spin glass behaviour, here we describe a system in which the structural disorder results in long-range antiferromagnetic order due to local symmetry breaking. Nd2ScNbO7is shown to have a dispersionless gapped excitation observed in other neodymium pyrochlores belowTN= 0.37 K through polarized and inelastic neutron scattering. However the dispersing spin waves are not observed. This excited mode is shown to occur in only 14(2)% of the neodymium ions through spectroscopy and is consistent with total scattering measurements as well as the magnitude of the dynamic moment 0.26(2)μB. The remaining magnetic species order completely into the all-in all-out Ising antiferromagnetic structure. This can be seen as a result of local symmetry breaking due disordered Sc+3and Nb+5ions about theA-site. From this work, it has been established thatB-site disorder restores the dipole-like behaviour of the Nd+3ions compared to the Nd2B2O7parent series.
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Affiliation(s)
- C Mauws
- Department of Chemistry, University of Manitoba, Winnipeg R3T 2N2, Canada
- Department of Chemistry, University of Winnipeg, Winnipeg R3B 2E9, Canada
| | - N Hiebert
- Department of Chemistry, University of Winnipeg, Winnipeg R3B 2E9, Canada
| | - M L Rutherford
- Department of Chemistry, University of Winnipeg, Winnipeg R3B 2E9, Canada
| | - H D Zhou
- Department of Physics and Astronomy, University of Tennessee-Knoxville, Knoxville 37996-1220, United States of America
- National High Magnetic Field Laboratory, Florida State University, Tallahassee 32306-4005, United States of America
| | - Q Huang
- Department of Physics and Astronomy, University of Tennessee-Knoxville, Knoxville 37996-1220, United States of America
| | - M B Stone
- Neutron Scattering Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States of America
| | - N P Butch
- Centre for Neutron Research, National Institute of Standards and Technology, 100 Bureau Drive, MS 6100, Gaithersburg, Maryland 20899, United States of America
| | - Y Su
- Jülich Centre for Neutron Science (JCNS) at Heinz Maier-Leibnitz Zentrum (MLZ), Forschungszentrum Jülich, Lichtenbergstrasse 1, 85747 Garching, Germany
| | - E S Choi
- National High Magnetic Field Laboratory, Florida State University, Tallahassee 32306-4005, United States of America
| | - Z Yamani
- Canadian Neutron Beam Centre, National Research Council of Canada, Chalk River, K0J 1P0, Canada
| | - C R Wiebe
- Department of Chemistry, University of Manitoba, Winnipeg R3T 2N2, Canada
- Department of Chemistry, University of Winnipeg, Winnipeg R3B 2E9, Canada
- Department of Physics and Astronomy, McMaster University, Hamilton L8S 4M1, Canada
- Centre for Science at Extreme Conditions, University of Edinburgh, Edinburgh EH9 3JZ, United Kingdom
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6
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Koch RJ, Sinclair R, McDonnell MT, Yu R, Abeykoon M, Tucker MG, Tsvelik AM, Billinge SJL, Zhou HD, Yin WG, Bozin ES. Dual Orbital Degeneracy Lifting in a Strongly Correlated Electron System. Phys Rev Lett 2021; 126:186402. [PMID: 34018766 DOI: 10.1103/physrevlett.126.186402] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Accepted: 03/29/2021] [Indexed: 06/12/2023]
Abstract
The local structure of NaTiSi_{2}O_{6} is examined across its Ti-dimerization orbital-assisted Peierls transition at 210 K. An atomic pair distribution function approach evidences local symmetry breaking preexisting far above the transition. The analysis unravels that, on warming, the dimers evolve into a short range orbital degeneracy lifted (ODL) state of dual orbital character, persisting up to at least 490 K. The ODL state is correlated over the length scale spanning ∼6 sites of the Ti zigzag chains. Results imply that the ODL phenomenology extends to strongly correlated electron systems.
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Affiliation(s)
- R J Koch
- Condensed Matter Physics and Materials Science Division, Brookhaven National Laboratory, Upton, New York 11973, USA
| | - R Sinclair
- Department of Physics and Astronomy, University of Tennessee, Knoxville, Tennessee 37996, USA
| | - M T McDonnell
- Neutron Scattering Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - R Yu
- Condensed Matter Physics and Materials Science Division, Brookhaven National Laboratory, Upton, New York 11973, USA
| | - M Abeykoon
- Photon Sciences Division, Brookhaven National Laboratory, Upton, New York 11973, USA
| | - M G Tucker
- Neutron Scattering Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - A M Tsvelik
- Condensed Matter Physics and Materials Science Division, Brookhaven National Laboratory, Upton, New York 11973, USA
| | - S J L Billinge
- Condensed Matter Physics and Materials Science Division, Brookhaven National Laboratory, Upton, New York 11973, USA
- Department of Applied Physics and Applied Mathematics, Columbia University, New York, New York 10027, USA
| | - H D Zhou
- Department of Physics and Astronomy, University of Tennessee, Knoxville, Tennessee 37996, USA
| | - W-G Yin
- Condensed Matter Physics and Materials Science Division, Brookhaven National Laboratory, Upton, New York 11973, USA
| | - E S Bozin
- Condensed Matter Physics and Materials Science Division, Brookhaven National Laboratory, Upton, New York 11973, USA
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7
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Shao S, Li XD, Lu YY, Li SJ, Chen XH, Zhou HD, He S, Guo YT, Lu X, Gao PJ, Wang JG. Renal Natriuretic Peptide Receptor-C Deficiency Attenuates NaCl Cotransporter Activity in Angiotensin II-Induced Hypertension. Hypertension 2021; 77:868-881. [PMID: 33486984 DOI: 10.1161/hypertensionaha.120.15636] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Genome-wide association studies have identified that NPR-C (natriuretic peptide receptor-C) variants are associated with elevation of blood pressure. However, the mechanism underlying the relationship between NPR-C and blood pressure regulation remains elusive. Here, we investigate whether NPR-C regulates Ang II (angiotensin II)-induced hypertension through sodium transporters activity. Wild-type mice responded to continuous Ang II infusion with an increased renal NPR-C expression. Global NPR-C deficiency attenuated Ang II-induced increased blood pressure both in male and female mice associated with more diuretic and natriuretic responses to a saline challenge. Interestingly, Ang II increased both total and phosphorylation of NCC (NaCl cotransporter) abundance involving in activation of WNK4 (with-no-lysine kinase 4)/SPAK (Ste20-related proline/alanine-rich kinase) which was blunted by NPR-C deletion. NCC inhibitor, hydrochlorothiazide, failed to induce natriuresis in NPR-C knockout mice. Moreover, low-salt and high-salt diets-induced changes of total and phosphorylation of NCC expression were normalized by NPR-C deletion. Importantly, tubule-specific deletion of NPR-C also attenuated Ang II-induced elevated blood pressure, total and phosphorylation of NCC expression. Mechanistically, in distal convoluted tubule cells, Ang II dose and time-dependently upregulated WNK4/SPAK/NCC kinase pathway and NPR-C/Gi/PLC/PKC signaling pathway mediated NCC activation. These results demonstrate that NPR-C signaling regulates NCC function contributing to sodium retention-mediated elevated blood pressure, which suggests that NPR-C is a promising candidate for the treatment of sodium retention-related hypertension.
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MESH Headings
- Angiotensin II
- Animals
- Blood Pressure/genetics
- Blood Pressure/physiology
- Cells, Cultured
- Female
- Hypertension/chemically induced
- Hypertension/genetics
- Hypertension/physiopathology
- Kidney/metabolism
- Kidney Tubules, Distal/cytology
- Kidney Tubules, Distal/metabolism
- Male
- Mice, Inbred C57BL
- Mice, Knockout
- Mice, Transgenic
- Protein Serine-Threonine Kinases/genetics
- Protein Serine-Threonine Kinases/metabolism
- Receptors, Atrial Natriuretic Factor/deficiency
- Receptors, Atrial Natriuretic Factor/genetics
- Renin-Angiotensin System/genetics
- Renin-Angiotensin System/physiology
- Signal Transduction/genetics
- Sodium/blood
- Sodium/urine
- Solute Carrier Family 12, Member 3/genetics
- Solute Carrier Family 12, Member 3/metabolism
- Mice
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Affiliation(s)
- Shuai Shao
- From the Department of Cardiovascular Medicine, Department of Hypertension, Ruijin Hospital and State Key Laboratory of Medical Genomics, Shanghai Key Laboratory of Hypertension, Shanghai Institute of Hypertension, Shanghai Jiao Tong University School of Medicine, China
| | - Xiao-Dong Li
- From the Department of Cardiovascular Medicine, Department of Hypertension, Ruijin Hospital and State Key Laboratory of Medical Genomics, Shanghai Key Laboratory of Hypertension, Shanghai Institute of Hypertension, Shanghai Jiao Tong University School of Medicine, China
| | - Yuan-Yuan Lu
- From the Department of Cardiovascular Medicine, Department of Hypertension, Ruijin Hospital and State Key Laboratory of Medical Genomics, Shanghai Key Laboratory of Hypertension, Shanghai Institute of Hypertension, Shanghai Jiao Tong University School of Medicine, China
| | - Shi-Jin Li
- From the Department of Cardiovascular Medicine, Department of Hypertension, Ruijin Hospital and State Key Laboratory of Medical Genomics, Shanghai Key Laboratory of Hypertension, Shanghai Institute of Hypertension, Shanghai Jiao Tong University School of Medicine, China
| | - Xiao-Hui Chen
- From the Department of Cardiovascular Medicine, Department of Hypertension, Ruijin Hospital and State Key Laboratory of Medical Genomics, Shanghai Key Laboratory of Hypertension, Shanghai Institute of Hypertension, Shanghai Jiao Tong University School of Medicine, China
| | - Han-Dan Zhou
- From the Department of Cardiovascular Medicine, Department of Hypertension, Ruijin Hospital and State Key Laboratory of Medical Genomics, Shanghai Key Laboratory of Hypertension, Shanghai Institute of Hypertension, Shanghai Jiao Tong University School of Medicine, China
| | - Shun He
- From the Department of Cardiovascular Medicine, Department of Hypertension, Ruijin Hospital and State Key Laboratory of Medical Genomics, Shanghai Key Laboratory of Hypertension, Shanghai Institute of Hypertension, Shanghai Jiao Tong University School of Medicine, China
| | - Yue-Tong Guo
- From the Department of Cardiovascular Medicine, Department of Hypertension, Ruijin Hospital and State Key Laboratory of Medical Genomics, Shanghai Key Laboratory of Hypertension, Shanghai Institute of Hypertension, Shanghai Jiao Tong University School of Medicine, China
| | - Xiao Lu
- From the Department of Cardiovascular Medicine, Department of Hypertension, Ruijin Hospital and State Key Laboratory of Medical Genomics, Shanghai Key Laboratory of Hypertension, Shanghai Institute of Hypertension, Shanghai Jiao Tong University School of Medicine, China
| | - Ping-Jin Gao
- From the Department of Cardiovascular Medicine, Department of Hypertension, Ruijin Hospital and State Key Laboratory of Medical Genomics, Shanghai Key Laboratory of Hypertension, Shanghai Institute of Hypertension, Shanghai Jiao Tong University School of Medicine, China
| | - Ji-Guang Wang
- From the Department of Cardiovascular Medicine, Department of Hypertension, Ruijin Hospital and State Key Laboratory of Medical Genomics, Shanghai Key Laboratory of Hypertension, Shanghai Institute of Hypertension, Shanghai Jiao Tong University School of Medicine, China
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8
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Jiao JL, Zhang HP, Huang Q, Wang W, Sinclair R, Wang G, Ren Q, Lin GT, Huq A, Zhou HD, Li MZ, Ma J. Orbital competition of Mn 3+ and V 3+ ions in Mn 1+x V 2-x O 4. J Phys Condens Matter 2021; 33:134002. [PMID: 33527912 DOI: 10.1088/1361-648x/abd9a1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
The structural and magnetic properties of Mn1+x V2-x O4 (0 < x ⩽ 1) have been investigated by the heat capacity, magnetization, x-ray diffraction and neutron diffraction measurements, and a phase diagram of temperature versus composition was built up. For x ⩽ 0.3, a cubic-to-tetragonal (c > a) phase transition was observed. For x > 0.3, the system maintained the tetragonal lattice. Although the collinear and noncollinear magnetic transitions of V3+ ions were obtained in all compositions, the canting angles between the V3+ ions decreased with Mn3+-doping, and the ordering of the Mn3+ ions was only observed as x > 0.4. In order to study the dynamics of the ground state, the first principles simulation was applied to analyze not only the orbital effects of Mn2+, Mn3+, and V3+ ions, but also the related exchange energies.
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Affiliation(s)
- J L Jiao
- Key Laboratory of Artificial Structures and Quantum Control (Ministry of Education), Shenyang National Laboratory for Materials Science, School of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240, People's Republic of China
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9
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Li N, Huang Q, Yue XY, Chu WJ, Chen Q, Choi ES, Zhao X, Zhou HD, Sun XF. Possible itinerant excitations and quantum spin state transitions in the effective spin-1/2 triangular-lattice antiferromagnet Na 2BaCo(PO 4) 2. Nat Commun 2020; 11:4216. [PMID: 32839456 PMCID: PMC7445251 DOI: 10.1038/s41467-020-18041-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2019] [Accepted: 08/03/2020] [Indexed: 11/09/2022] Open
Abstract
The most fascinating feature of certain two-dimensional (2D) gapless quantum spin liquid (QSL) is that their spinon excitations behave like the fermionic carriers of a paramagnetic metal. The spinon Fermi surface is then expected to produce a linear increase of the thermal conductivity with temperature that should manifest via a residual value (κ0/T) in the zero-temperature limit. However, this linear in T behavior has been reported for very few QSL candidates. Here, we studied the ultralow-temperature thermal conductivity of an effective spin-1/2 triangular QSL candidate Na2BaCo(PO4)2, which has an antiferromagnetic order at very low temperature (TN ~ 148 mK), and observed a finite κ0/T extrapolated from the data above TN. Moreover, while approaching zero temperature, it exhibits series of quantum spin state transitions with applied field along the c axis. These observations indicate that Na2BaCo(PO4)2 possibly behaves as a gapless QSL with itinerant spin excitations above TN and its strong quantum spin fluctuations persist below TN.
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Affiliation(s)
- N Li
- Hefei National Laboratory for Physical Sciences at Microscale, Department of Physics, and Key Laboratory of Strongly-Coupled Quantum Matter Physics (CAS), University of Science and Technology of China, 230026, Hefei, Anhui, People's Republic of China
| | - Q Huang
- Department of Physics and Astronomy, University of Tennessee, Knoxville, TN, 37996-1200, USA
| | - X Y Yue
- Institute of Physical Science and Information Technology, Anhui University, 230601, Hefei, Anhui, People's Republic of China
| | - W J Chu
- Hefei National Laboratory for Physical Sciences at Microscale, Department of Physics, and Key Laboratory of Strongly-Coupled Quantum Matter Physics (CAS), University of Science and Technology of China, 230026, Hefei, Anhui, People's Republic of China
| | - Q Chen
- Department of Physics and Astronomy, University of Tennessee, Knoxville, TN, 37996-1200, USA
| | - E S Choi
- National High Magnetic Field Laboratory, Florida State University, Tallahassee, FL, 32310-3706, USA
| | - X Zhao
- School of Physical Sciences, University of Science and Technology of China, 230026, Hefei, Anhui, People's Republic of China
| | - H D Zhou
- Department of Physics and Astronomy, University of Tennessee, Knoxville, TN, 37996-1200, USA.
| | - X F Sun
- Hefei National Laboratory for Physical Sciences at Microscale, Department of Physics, and Key Laboratory of Strongly-Coupled Quantum Matter Physics (CAS), University of Science and Technology of China, 230026, Hefei, Anhui, People's Republic of China. .,Institute of Physical Science and Information Technology, Anhui University, 230601, Hefei, Anhui, People's Republic of China.
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10
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Jiang Y, Wang J, Zhao T, Dun ZL, Huang Q, Wu XS, Mourigal M, Zhou HD, Pan W, Ozerov M, Smirnov D, Jiang Z. Unraveling the Topological Phase of ZrTe_{5} via Magnetoinfrared Spectroscopy. Phys Rev Lett 2020; 125:046403. [PMID: 32794786 DOI: 10.1103/physrevlett.125.046403] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2020] [Revised: 06/04/2020] [Accepted: 07/07/2020] [Indexed: 06/11/2023]
Abstract
For materials near the phase boundary between weak and strong topological insulators (TIs), their band topology depends on the band alignment, with the inverted (normal) band corresponding to the strong (weak) TI phase. Here, taking the anisotropic transition-metal pentatelluride ZrTe_{5} as an example, we show that the band inversion manifests itself as a second extremum (band gap) in the layer stacking direction, which can be probed experimentally via magnetoinfrared spectroscopy. Specifically, we find that the band anisotropy of ZrTe_{5} features a slow dispersion in the layer stacking direction, along with an additional set of optical transitions from a band gap next to the Brillouin zone center. Our work identifies ZrTe_{5} as a strong TI at liquid helium temperature and provides a new perspective in determining band inversion in layered topological materials.
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Affiliation(s)
- Y Jiang
- National High Magnetic Field Laboratory, Tallahassee, Florida 32310, USA
| | - J Wang
- School of Physics, Georgia Institute of Technology, Atlanta, Georgia 30332, USA
- State Key Laboratory for Artificial Microstructure and Mesoscopic Physics, Peking University, Beijing 100871, China
| | - T Zhao
- School of Physics, Georgia Institute of Technology, Atlanta, Georgia 30332, USA
| | - Z L Dun
- School of Physics, Georgia Institute of Technology, Atlanta, Georgia 30332, USA
| | - Q Huang
- Department of Physics and Astronomy, University of Tennessee, Knoxville, Tennessee 37996, USA
| | - X S Wu
- State Key Laboratory for Artificial Microstructure and Mesoscopic Physics, Peking University, Beijing 100871, China
| | - M Mourigal
- School of Physics, Georgia Institute of Technology, Atlanta, Georgia 30332, USA
| | - H D Zhou
- Department of Physics and Astronomy, University of Tennessee, Knoxville, Tennessee 37996, USA
| | - W Pan
- Quantum and Electronic Materials Department, Sandia National Laboratories, Livermore, California 94551, USA
| | - M Ozerov
- National High Magnetic Field Laboratory, Tallahassee, Florida 32310, USA
| | - D Smirnov
- National High Magnetic Field Laboratory, Tallahassee, Florida 32310, USA
| | - Z Jiang
- School of Physics, Georgia Institute of Technology, Atlanta, Georgia 30332, USA
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11
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Zhou HD, Jiang HF, Zhu YJ, Shen J, Fang J. [Effects of dexmedetomidine on cerebral oxygen saturation and postoperative revival period in elderly patients with ovarian cancer]. Zhonghua Yi Xue Za Zhi 2019; 98:3584-3586. [PMID: 30486574 DOI: 10.3760/cma.j.issn.0376-2491.2018.44.007] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Objective: To observe the effects of dexmedetomidine on cerebral oxygen saturation and postoperative recovery in elderly patients with ovarian cancer. Methods: Sixty elderly patients with ovarian cancer were randomly divided into two groups. Both groups were given total intravenous anesthesia. Patients in group D were given a loading dosage of dexmedetomidine 0.5 μg/kg, followed by continuous infusion 0.2 μg·kg(-1)·h(-1) until 30 minutes before the end of operation. Group C were given normal saline at the same time. The cerebral oxygen saturation was observed and recorded before anaesthesia (T0), an hour after operation (T1), the end of operation (T2) and 30 min after tracheal extubation (T3). The time of extubation and adverse reactions such as restlessness, shivering and respiratory inhibition were observed in both groups. Results: There was no significant difference in cerebral oxygen saturation between the two groups at different time points (P>0.05), and the degree of restlessness and its incidence in group D were lower than those in group C, and the adverse reactions such as shivering were lower (P<0.05). Conclusion: Dexmedetomidine has no obvious effect on cerebral oxygen saturation in elderly patients with ovarian cancer. It can effectively prevent and reduce postoperative restlessness, does not affect recovery time, and has fewer adverse reactions.
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Affiliation(s)
- H D Zhou
- Department of Anesthesiology, Zhejiang Cancer Hospital, Hangzhou 310022, China
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12
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Kamiya Y, Ge L, Hong T, Qiu Y, Quintero-Castro DL, Lu Z, Cao HB, Matsuda M, Choi ES, Batista CD, Mourigal M, Zhou HD, Ma J. Author Correction: The nature of spin excitations in the one-third magnetization plateau phase of Ba 3CoSb 2O 9. Nat Commun 2018; 9:3110. [PMID: 30068947 PMCID: PMC6070534 DOI: 10.1038/s41467-018-05679-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Affiliation(s)
- Y Kamiya
- Condensed Matter Theory Laboratory, RIKEN, Wako, 351-0198, Saitama, Japan.
| | - L Ge
- School of Physics, Georgia Institute of Technology, 30332, Atlanta, GA, USA
| | - Tao Hong
- Neutron Scattering Division, Oak Ridge National Laboratory, 37831, Oak Ridge, TN, USA
| | - Y Qiu
- NIST Centre for Neutron Research, National Institute of Standards and Technology, 20899, Gaithersburg, MD, USA
| | - D L Quintero-Castro
- Helmholtz-Zentrum Berlin für Materialien und Energie, D-14109, Berlin, Germany
| | - Z Lu
- Helmholtz-Zentrum Berlin für Materialien und Energie, D-14109, Berlin, Germany
| | - H B Cao
- Neutron Scattering Division, Oak Ridge National Laboratory, 37831, Oak Ridge, TN, USA
| | - M Matsuda
- Neutron Scattering Division, Oak Ridge National Laboratory, 37831, Oak Ridge, TN, USA
| | - E S Choi
- National High Magnetic Field Laboratory, Florida State University, 32310, Tallahassee, FL, USA
| | - C D Batista
- Department of Physics and Astronomy, University of Tennessee, 37996, Knoxville, TN, USA.,Neutron Scattering Division and Shull-Wollan Center, Oak Ridge National Laboratory, 37831, Oak Ridge, TN, USA
| | - M Mourigal
- School of Physics, Georgia Institute of Technology, 30332, Atlanta, GA, USA
| | - H D Zhou
- National High Magnetic Field Laboratory, Florida State University, 32310, Tallahassee, FL, USA.,Department of Physics and Astronomy, University of Tennessee, 37996, Knoxville, TN, USA
| | - J Ma
- Department of Physics and Astronomy, University of Tennessee, 37996, Knoxville, TN, USA. .,Key Laboratory of Artificial Structures and Quantum Control, Department of Physics and Astronomy, Shanghai Jiao Tong University, 200240, Shanghai, China. .,Collaborative Innovation Center of Advanced Microstructures, 210093, Nanjing, Jiangsu, China.
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13
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Kamiya Y, Ge L, Hong T, Qiu Y, Quintero-Castro DL, Lu Z, Cao HB, Matsuda M, Choi ES, Batista CD, Mourigal M, Zhou HD, Ma J. The nature of spin excitations in the one-third magnetization plateau phase of Ba 3CoSb 2O 9. Nat Commun 2018; 9:2666. [PMID: 29991805 PMCID: PMC6039502 DOI: 10.1038/s41467-018-04914-1] [Citation(s) in RCA: 45] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2017] [Accepted: 05/21/2018] [Indexed: 11/25/2022] Open
Abstract
Magnetization plateaus in quantum magnets—where bosonic quasiparticles crystallize into emergent spin superlattices—are spectacular yet simple examples of collective quantum phenomena escaping classical description. While magnetization plateaus have been observed in a number of spin-1/2 antiferromagnets, the description of their magnetic excitations remains an open theoretical and experimental challenge. Here, we investigate the dynamical properties of the triangular-lattice spin-1/2 antiferromagnet Ba3CoSb2O9 in its one-third magnetization plateau phase using a combination of nonlinear spin-wave theory and neutron scattering measurements. The agreement between our theoretical treatment and the experimental data demonstrates that magnons behave semiclassically in the plateau in spite of the purely quantum origin of the underlying magnetic structure. This allows for a quantitative determination of Ba3CoSb2O9 exchange parameters. We discuss the implication of our results to the deviations from semiclassical behavior observed in zero-field spin dynamics of the same material and conclude they must have an intrinsic origin. Frustrated magnetic materials attract significant interest because their properties can become dominated by quantum fluctuations. Here the authors show that excitations in the plateau phase of a quantum magnet can be understood semiclassically even though the ground state involves strong quantum effects.
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Affiliation(s)
- Y Kamiya
- Condensed Matter Theory Laboratory, RIKEN, Wako, Saitama, 351-0198, Japan.
| | - L Ge
- School of Physics, Georgia Institute of Technology, Atlanta, GA, 30332, USA
| | - Tao Hong
- Neutron Scattering Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA
| | - Y Qiu
- NIST Centre for Neutron Research, National Institute of Standards and Technology, Gaithersburg, MD, 20899, USA
| | - D L Quintero-Castro
- Helmholtz-Zentrum Berlin für Materialien und Energie, D-14109, Berlin, Germany
| | - Z Lu
- Helmholtz-Zentrum Berlin für Materialien und Energie, D-14109, Berlin, Germany
| | - H B Cao
- Neutron Scattering Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA
| | - M Matsuda
- Neutron Scattering Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA
| | - E S Choi
- National High Magnetic Field Laboratory, Florida State University, Tallahassee, FL, 32310, USA
| | - C D Batista
- Department of Physics and Astronomy, University of Tennessee, Knoxville, TN, 37996, USA.,Neutron Scattering Division and Shull-Wollan Center, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA
| | - M Mourigal
- School of Physics, Georgia Institute of Technology, Atlanta, GA, 30332, USA
| | - H D Zhou
- National High Magnetic Field Laboratory, Florida State University, Tallahassee, FL, 32310, USA.,Department of Physics and Astronomy, University of Tennessee, Knoxville, TN, 37996, USA
| | - J Ma
- Department of Physics and Astronomy, University of Tennessee, Knoxville, TN, 37996, USA. .,Key Laboratory of Artificial Structures and Quantum Control, Department of Physics and Astronomy, Shanghai Jiao Tong University, 200240, Shanghai, China. .,Collaborative Innovation Center of Advanced Microstructures, 210093, Nanjing, Jiangsu, China.
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14
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Zhou HD, Jiang HF, Zhu YJ, Fang J. [Clinical application of oxycodone combined with dexmedetomidine in percutaneous ultrasound-guided radiofrequency ablation of hepatocellular carcinomas]. Zhonghua Yi Xue Za Zhi 2018; 97:3480-3482. [PMID: 29275583 DOI: 10.3760/cma.j.issn.0376-2491.2017.44.009] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Objective: To explore the effects of oxycodone combined with dexmedetomidine in percutaneous ultrasound-guided radiofrequency ablation of hepatocellular carcinomas. Methods: Sixty patients who underwent percutaneous ultrasound-guided radiofrequency ablation of hepatocellular carcinomas were randomly divided into fentanyl group (group A) and oxycodone group( group B), with 30 patients in each group. Patients in group A were injected with fentanyl (2 μg/kg), and patients in group B were injected with oxycodone (0.2 mg/kg). All the patients were injected with dexmedetomidine, with a loading dose of 0.5 μg/kg for 10 minutes and a continuous infusion rate of 0.2 μg·kg(-1)·h(-1) until the end of the operation. The changes of heart rate (HR), mean arterial pressure (MAP), pulse oxygen saturation (SPO(2)) and bispectral index (BIS) were monitored at different time points: time when patients entering the operating room (T0), the beginning of operation (T1), 10 minutes after operation (T2), the end of operation (T3), 15 minutes after the end of operation (T4). The incidence of side effects (nausea and vomiting, respiratory depression and body movements) was assessed. The visual analogue scale (VAS) scores were also recorded at T0, T3 and an hour postoperatively. Results: Five patients of Group A had the body movements during the operation, and it was improved after injecting with fentanyl 2 μg/kg. Compared with T0, HR in two groups decreased significantly at T2 (P<0.05). At each time point, the difference of MAP, HR, SPO(2) and BIS was not statistically significant in two groups. The incidence of Nausea and vomiting, body movements was lower in group B than that in group A(P<0.05). The VAS scores were lower in group B than that in group A at T3 and an hour postoperatively (P<0.05). Conclusion: The combination of oxycodone and dexmedetomidine can be used safely and effectively in percutaneous ultrasound-guided radiofrequency ablation of hepatocellular carcinomas, and it shows more effective analgesia and less side-effects.
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Affiliation(s)
- H D Zhou
- Department of Anesthesiology, Zhejiang Cancer Hospital, Hangzhou 310022, China
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15
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Akbari-Sharbaf A, Sinclair R, Verrier A, Ziat D, Zhou HD, Sun XF, Quilliam JA. Tunable Quantum Spin Liquidity in the 1/6th-Filled Breathing Kagome Lattice. Phys Rev Lett 2018; 120:227201. [PMID: 29906141 DOI: 10.1103/physrevlett.120.227201] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2017] [Revised: 03/23/2018] [Indexed: 06/08/2023]
Abstract
We present measurements on a series of materials, Li_{2}In_{1-x}Sc_{x}Mo_{3}O_{8}, that can be described as a 1/6th-filled breathing kagome lattice. Substituting Sc for In generates chemical pressure which alters the breathing parameter nonmonotonically. Muon spin rotation experiments show that this chemical pressure tunes the system from antiferromagnetic long range order to a quantum spin liquid phase. A strong correlation with the breathing parameter implies that it is the dominant parameter controlling the level of magnetic frustration, with increased kagome symmetry generating the quantum spin liquid phase. Magnetic susceptibility measurements suggest that this is related to distinct types of charge order induced by changes in lattice symmetry, in line with the theory of Chen et al. [Phys. Rev. B 93, 245134 (2016)PRBMDO2469-995010.1103/PhysRevB.93.245134]. The specific heat for samples at intermediate Sc concentration, which have the minimum breathing parameter, show consistency with the predicted U(1) quantum spin liquid.
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Affiliation(s)
- A Akbari-Sharbaf
- Institut Quantique and Département de Physique, Université de Sherbrooke, 2500 boulevard de l'Université, Sherbrooke, Québec J1K 2R1, Canada
| | - R Sinclair
- Department of Physics and Astronomy, University of Tennessee, Knoxville, Tennessee 37996-1200, USA
| | - A Verrier
- Institut Quantique and Département de Physique, Université de Sherbrooke, 2500 boulevard de l'Université, Sherbrooke, Québec J1K 2R1, Canada
| | - D Ziat
- Institut Quantique and Département de Physique, Université de Sherbrooke, 2500 boulevard de l'Université, Sherbrooke, Québec J1K 2R1, Canada
| | - H D Zhou
- Department of Physics and Astronomy, University of Tennessee, Knoxville, Tennessee 37996-1200, USA
- Key Laboratory of Artificial Structures and Quantum Control, Ministry of Education, School of Physics and Astronomy, Shanghai JiaoTong University, Shanghai 200240, China
| | - X F Sun
- Department of Physics, Hefei National Laboratory for Physical Sciences at Microscale and Key Laboratory of Strongly-Coupled Quantum Matter Physics, CAS, University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China
- Institute of Physical Science and Information Technology, Anhui University, Hefei, Anhui 230601, People's Republic of China
- Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, Jiangsu 210093, People's Republic of China
| | - J A Quilliam
- Institut Quantique and Département de Physique, Université de Sherbrooke, 2500 boulevard de l'Université, Sherbrooke, Québec J1K 2R1, Canada
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16
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Gu CC, Zhao ZY, Chen XL, Lee M, Choi ES, Han YY, Ling LS, Pi L, Zhang YH, Chen G, Yang ZR, Zhou HD, Sun XF. Field-Driven Quantum Criticality in the Spinel Magnet ZnCr_{2}Se_{4}. Phys Rev Lett 2018; 120:147204. [PMID: 29694140 DOI: 10.1103/physrevlett.120.147204] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/19/2017] [Revised: 03/08/2018] [Indexed: 06/08/2023]
Abstract
We report detailed dc and ac magnetic susceptibilities, specific heat, and thermal conductivity measurements on the frustrated magnet ZnCr_{2}Se_{4}. At low temperatures, with an increasing magnetic field, this spinel material goes through a series of spin state transitions from the helix spin state to the spiral spin state and then to the fully polarized state. Our results indicate a direct quantum phase transition from the spiral spin state to the fully polarized state. As the system approaches the quantum criticality, we find strong quantum fluctuations of the spins with behaviors such as an unconventional T^{2}-dependent specific heat and temperature-independent mean free path for the thermal transport. We complete the full phase diagram of ZnCr_{2}Se_{4} under the external magnetic field and propose the possibility of frustrated quantum criticality with extended densities of critical modes to account for the unusual low-energy excitations in the vicinity of the criticality. Our results reveal that ZnCr_{2}Se_{4} is a rare example of a 3D magnet exhibiting a field-driven quantum criticality with unconventional properties.
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Affiliation(s)
- C C Gu
- Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory, Chinese Academy of Sciences, Hefei, Anhui 230031, People's Republic of China
| | - Z Y Zhao
- Department of Physics, Hefei National Laboratory for Physical Sciences at Microscale, and Key Laboratory of Strongly-Coupled Quantum Matter Physics (CAS), University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China
- Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, Fujian 350002, People's Republic of China
| | - X L Chen
- Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory, Chinese Academy of Sciences, Hefei, Anhui 230031, People's Republic of China
| | - M Lee
- National High Magnetic Field Laboratory, Florida State University, Tallahassee, Florida 32306-4005, USA
- Department of Physics, Florida State University, Tallahassee, Florida 32306-3016, USA
| | - E S Choi
- National High Magnetic Field Laboratory, Florida State University, Tallahassee, Florida 32306-4005, USA
| | - Y Y Han
- Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory, Chinese Academy of Sciences, Hefei, Anhui 230031, People's Republic of China
| | - L S Ling
- Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory, Chinese Academy of Sciences, Hefei, Anhui 230031, People's Republic of China
| | - L Pi
- Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory, Chinese Academy of Sciences, Hefei, Anhui 230031, People's Republic of China
- Department of Physics, Hefei National Laboratory for Physical Sciences at Microscale, and Key Laboratory of Strongly-Coupled Quantum Matter Physics (CAS), University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China
- Collaborative Innovation Center of Advanced Microstructures, Nanjing, Jiangsu 210093, People's Republic of China
| | - Y H Zhang
- Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory, Chinese Academy of Sciences, Hefei, Anhui 230031, People's Republic of China
- Collaborative Innovation Center of Advanced Microstructures, Nanjing, Jiangsu 210093, People's Republic of China
| | - G Chen
- State Key Laboratory of Surface Physics and Department of Physics, Center for Field Theory and Particle Physics, Fudan University, Shanghai, 200433, China
- Collaborative Innovation Center of Advanced Microstructures, Nanjing, Jiangsu 210093, People's Republic of China
| | - Z R Yang
- Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory, Chinese Academy of Sciences, Hefei, Anhui 230031, People's Republic of China
- Collaborative Innovation Center of Advanced Microstructures, Nanjing, Jiangsu 210093, People's Republic of China
- Institute of Physical Science and Information Technology, Anhui University, Hefei, Anhui 230601, People's Republic of China
| | - H D Zhou
- Key laboratory of Artificial Structures and Quantum Control (Ministry of Education), School of Physics and Astronomy, Shanghai JiaoTong University, Shanghai 200240, China
- Department of Physics and Astronomy, University of Tennessee, Knoxville, Tennessee 37996-1200, USA
| | - X F Sun
- Department of Physics, Hefei National Laboratory for Physical Sciences at Microscale, and Key Laboratory of Strongly-Coupled Quantum Matter Physics (CAS), University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China
- Collaborative Innovation Center of Advanced Microstructures, Nanjing, Jiangsu 210093, People's Republic of China
- Institute of Physical Science and Information Technology, Anhui University, Hefei, Anhui 230601, People's Republic of China
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17
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Zhou HD, Sarte PM, Conner BS, Balicas L, Wiebe CR, Chen XH, Wu T, Wu G, Liu RH, Chen H, Fang DF. Evidence for negative thermal expansion in the superconducting precursor phase SmFeAsO. J Phys Condens Matter 2018; 30:095601. [PMID: 29431150 DOI: 10.1088/1361-648x/aaa3b0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
The fluorine-doped rare-earth iron oxypnictide series SmFeAsO1-x F x (0 [Formula: see text] 0.10) was investigated with high resolution powder x-ray scattering. In agreement with previous studies (Margadonna et al 2009 Phys. Rev. B. 79 014503), the parent compound SmFeAsO exhibits a tetragonal-to-orthorhombic structural distortion at [Formula: see text] = 130 K which is rapidly suppressed by [Formula: see text] 0.10 deep within the superconducting dome. The change in unit cell symmetry is followed by a previously unreported magnetoelastic distortion at 120 K. The temperature dependence of the thermal expansion coefficient [Formula: see text] reveals a rich phase diagram for SmFeAsO: (i) a global minimum at 125 K corresponds to the opening of a spin-density wave instability as measured by pump-probe femtosecond spectroscopy (Mertelj et al 2010 Phys. Rev. B 81 224504) whilst (ii) a global maximum at 110 K corresponds to magnetic ordering of the Sm and Fe sublattices as measured by magnetic x-ray scattering (Nandi et al 2011 Phys. Rev. B 84 055419). At much lower temperatures than [Formula: see text], SmFeAsO exhibits a significant negative thermal expansion on the order of -40 ppm · K-1 in contrast to the behaviour of other rare-earth oxypnictides such as PrFeAsO (Kimber et al 2008 Phys. Rev. B 78 140503) and the actinide oxypnictide NpFeAsO (Klimczuk et al 2012 Phys. Rev. B 85 174506) where the onset of [Formula: see text] 0 only appears in the vicinity of magnetic ordering. Correlating this feature with the temperature and doping dependence of the resistivity and the unit cell parameters, we interpret the negative thermal expansion as being indicative of the possible condensation of itinerant electrons accompanying the opening of a SDW gap, consistent with transport measurements (Tropeano et al 2009 Supercond. Sci. Technol. 22 034004).
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Affiliation(s)
- H D Zhou
- Department of Physics and Astronomy, University of Tennessee, Knoxville, TN 37996, United States of America
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18
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Lee JH, Ma J, Hahn SE, Cao HB, Lee M, Hong T, Lee HJ, Yeom MS, Okamoto S, Zhou HD, Matsuda M, Fishman RS. Magnetic Frustration Driven by Itinerancy in Spinel CoV 2O 4. Sci Rep 2017; 7:17129. [PMID: 29215077 PMCID: PMC5719412 DOI: 10.1038/s41598-017-17160-0] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2015] [Accepted: 11/13/2017] [Indexed: 11/12/2022] Open
Abstract
Localized spins and itinerant electrons rarely coexist in geometrically-frustrated spinel lattices. They exhibit a complex interplay between localized spins and itinerant electrons. In this paper, we study the origin of the unusual spin structure of the spinel CoV2O4, which stands at the crossover from insulating to itinerant behavior using the first principle calculation and neutron diffraction measurement. In contrast to the expected paramagnetism, localized spins supported by enhanced exchange couplings are frustrated by the effects of delocalized electrons. This frustration produces a non-collinear spin state even without orbital orderings and may be responsible for macroscopic spin-glass behavior. Competing phases can be uncovered by external perturbations such as pressure or magnetic field, which enhances the frustration.
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Affiliation(s)
- J H Lee
- School of Energy and Chemical Engineering, Ulsan National Institute of Science and Technology, Ulsan, 44919, Republic of Korea.
| | - J Ma
- Department of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai, 200240, China.,Key Laboratory of Artificial Structures and Quantum Control, School of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - S E Hahn
- Neutron Data Analysis and Visualization Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee, 37831, USA.,Quantum Condensed Matter Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee, 37831, USA
| | - H B Cao
- Quantum Condensed Matter Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee, 37831, USA
| | - M Lee
- School of Energy and Chemical Engineering, Ulsan National Institute of Science and Technology, Ulsan, 44919, Republic of Korea
| | - Tao Hong
- Quantum Condensed Matter Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee, 37831, USA
| | - H-J Lee
- School of Energy and Chemical Engineering, Ulsan National Institute of Science and Technology, Ulsan, 44919, Republic of Korea
| | - M S Yeom
- Department of Applied Research and Network R&D, Center for Computational Science and Engineering, Division of National Supercomputing R&D, Korea Institute of Science and Technology Information (KISTI), 245 Daehak-ro, Daejeon, 34141, Republic of Korea.
| | - S Okamoto
- Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee, 37831, USA
| | - H D Zhou
- Department of Physics and Astronomy, University of Tennessee, Knoxville, Tennessee, 37996, USA
| | - M Matsuda
- Quantum Condensed Matter Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee, 37831, USA
| | - R S Fishman
- Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee, 37831, USA
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19
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Sarte PM, Aczel AA, Ehlers G, Stock C, Gaulin BD, Mauws C, Stone MB, Calder S, Nagler SE, Hollett JW, Zhou HD, Gardner JS, Attfield JP, Wiebe CR. Evidence for the confinement of magnetic monopoles in quantum spin ice. J Phys Condens Matter 2017; 29:45LT01. [PMID: 29049030 DOI: 10.1088/1361-648x/aa8ec2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Magnetic monopoles are hypothesised elementary particles connected by Dirac strings that behave like infinitely thin solenoids (Dirac 1931 Proc. R. Soc. A 133 60). Despite decades of searching, free magnetic monopoles and their Dirac strings have eluded experimental detection, although there is substantial evidence for deconfined magnetic monopole quasiparticles in spin ice materials (Castelnovo et al 2008 Nature 326 411). Here we report the detection of a hierarchy of unequally-spaced magnetic excitations via high resolution inelastic neutron spectroscopic measurements on the quantum spin ice candidate [Formula: see text] [Formula: see text] [Formula: see text]. These excitations are well-described by a simple model of monopole pairs bound by a linear potential (Coldea et al Science 327 177) with an effective tension of 0.642(8) K [Formula: see text] at 1.65 K. The success of the linear potential model suggests that these low energy magnetic excitations are direct spectroscopic evidence for the confinement of magnetic monopole quasiparticles in the quantum spin ice candidate [Formula: see text] [Formula: see text] [Formula: see text].
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Affiliation(s)
- P M Sarte
- School of Chemistry, University of Edinburgh, Edinburgh EH9 3FJ, United Kingdom. Centre for Science at Extreme Conditions, University of Edinburgh, Edinburgh EH9 3FD, United Kingdom
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20
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Zhao ZY, Wu Y, Cao HB, Zhou HD, Yan JQ. Three-dimensional magnetic interactions in quasi-two-dimensional PdAs 2O 6. J Phys Condens Matter 2017; 29:235801. [PMID: 28443827 DOI: 10.1088/1361-648x/aa6f9d] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Millimeter-sized PdAs2O6 single crystals are grown using the vapor transport technique. The magnetic order at [Formula: see text] K is studied by measuring magnetic properties, specific heat, and neutron single crystal diffraction. The anisotropic magnetic susceptibility and a metamagnetic transition observed in magnetic fields above 20 kOe suggest that the magnetic moment lies in the ab plane, consistent with the magnetic structure determined by neutron single crystal diffraction. Below 140 K, Pd2+ ions order ferromagnetically in the ab plane but antiferromagnetically along the crystallographic c axis. The ordered moment is refined to be 2.09(2) [Formula: see text]/Pd2+ using the fitted magnetic form factor of Pd2+ . A weak λ-type anomaly around T N was observed in specific heat and the magnetic entropy change across T N is 1.72 J mol-1 K.This small entropy change and the temperature dependence of the magnetic susceptibility support the presence of short range correlations in a wide temperature range [Formula: see text] 250 K. The comparison with SrRu2O6 suggests that the magnetic interactions in PdAs2O6 are dominated by Pd-(O-[Formula: see text]-O)-Pd super-superexchange and three dimensional despite the quasi-two-dimensional arrangement of magnetic ions. The comparison with NiAs2O6 suggests that increasing covalency of isostructural compounds is an effective approach to design and to discover new materials with higher magnetic order temperatures in the localized regime.
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Affiliation(s)
- Z Y Zhao
- Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, United States of America. Department of Physics and Astronomy, University of Tennessee, Knoxville, TN 37996, United States of America
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21
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Sinclair R, Cao HB, Garlea VO, Lee M, Choi ES, Dun ZL, Dong S, Dagotto E, Zhou HD. Canted magnetic ground state of quarter-doped manganites R 0.75Ca 0.25MnO 3 (R = Y, Tb, Dy, Ho, and Er). J Phys Condens Matter 2017; 29:065802. [PMID: 28002058 DOI: 10.1088/1361-648x/aa4de1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Polycrystalline samples of the quarter-doped manganites R 0.75Ca0.25MnO3 (R = Y, Tb, Dy, Ho, and Er) were studied by x-ray diffraction and AC/DC susceptibility measurements. All five samples are orthorhombic and exhibit similar magnetic properties: enhanced ferromagnetism below T 1 (∼80 K) and a spin glass (SG) state below T SG (∼30 K). With increasing R 3+ ionic size, both T 1 and T SG generally increase. The single crystal neutron diffraction results on Tb0.75Ca0.25MnO3 revealed that the SG state is mainly composed of a short-range ordered version of a novel canted (i.e. noncollinear) antiferromagnetic spin state. Furthermore, calculations based on the double exchange model for quarter-doped manganites reveal that this new magnetic phase provides a transition state between the ferromagnetic state and the theoretically predicted spin-orthogonal stripe phase.
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Affiliation(s)
- R Sinclair
- Department of Physics and Astronomy, University of Tennessee, Knoxville, TN 37996-1200, USA
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22
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Lee M, Choi ES, Ma J, Sinclair R, Dela Cruz CR, Zhou HD. Magnetism and multiferroicity of an isosceles triangular lattice antiferromagnet Sr3NiNb2O9. J Phys Condens Matter 2016; 28:476004. [PMID: 27661860 DOI: 10.1088/0953-8984/28/47/476004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Various experimental measurements were performed to complete the phase diagram of a weakly distorted triangular lattice system, Sr3NiNb2O9 with Ni(2+) , spin-1 magnetic ions. This compound possesses an isosceles triangular lattice with two shorter bonds and one longer bond. It shows a two-step magnetic phase transition at [Formula: see text] K and [Formula: see text] K at zero magnetic field, characteristic of an easy-axis anisotropy. In the magnetization curves, a series of magnetic phase transitions was observed such as an up-up-down phase at [Formula: see text] T with 1/3 of the saturation magnetization (M sat) and an oblique phase at [Formula: see text] T with [Formula: see text]/3 M sat. Intriguingly, the magnetic phase transition below T N2 is in tandem with the ferroelectricity, which demonstrates multiferroic behaviors. Moreover, the multiferroic phase persists in all magnetically ordered phases regardless of the spin structure. The comparison between the phase diagrams of Sr3NiNb2O9 and its sister compound with an equilateral triangular lattice antiferromagnet Ba3NiNb2O9 (Hwang et al 2012 Phys. Rev. Lett. 109 257205), illustrates how a small imbalance among exchange interactions change the magnetic ground states of the TLAFs.
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Affiliation(s)
- M Lee
- Department of Physics, Florida State University, Tallahassee, FL 32306-3016, USA. National High Magnetic Field Laboratory, Florida State University, Tallahassee, FL 32310-3706, USA
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23
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Dun ZL, Trinh J, Li K, Lee M, Chen KW, Baumbach R, Hu YF, Wang YX, Choi ES, Shastry BS, Ramirez AP, Zhou HD. Magnetic Ground States of the Rare-Earth Tripod Kagome Lattice Mg_{2}RE_{3}Sb_{3}O_{14} (RE=Gd,Dy,Er). Phys Rev Lett 2016; 116:157201. [PMID: 27127982 DOI: 10.1103/physrevlett.116.157201] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/08/2016] [Indexed: 06/05/2023]
Abstract
We present the structural and magnetic properties of a new compound family, Mg_{2}RE_{3}Sb_{3}O_{14} (RE=Gd,Dy,Er), with a hitherto unstudied frustrating lattice, the "tripod kagome" structure. Susceptibility (ac, dc) and specific heat exhibit features that are understood within a simple Luttinger-Tisza-type theory. For RE=Gd, we found long-ranged order (LRO) at 1.65 K, which is consistent with a 120° structure, demonstrating the importance of diople interactions for this 2D Heisenberg system. For RE=Dy, LRO at 0.37 K is related to the "kagome spin ice" physics for a 2D system. This result shows that the tripod kagome structure accelerates the transition to LRO predicted for the related pyrochlore systems. For RE=Er, two transitions, at 80 mK and 2.1 K are observed, suggesting the importance of quantum fluctuations for this putative XY system.
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Affiliation(s)
- Z L Dun
- Department of Physics and Astronomy, University of Tennessee, Knoxville, Tennessee 37996-1200, USA
| | - J Trinh
- Department of Physics, University of California, Santa Cruz, California 95064, USA
| | - K Li
- Beijing National Laboratory for Molecular Sciences, State Key Laboratory of Rare Earth Materials Chemistry and Applications, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, People's Republic of China
- Center for High Pressure Science and Technology Advanced Research, Beijing 100094, People's Republic of China
| | - M Lee
- Department of Physics, Florida State University, Tallahassee, Florida 32306-3016, USA
- National High Magnetic Field Laboratory, Florida State University, Tallahassee, Florida 32310-3706, USA
| | - K W Chen
- National High Magnetic Field Laboratory, Florida State University, Tallahassee, Florida 32310-3706, USA
| | - R Baumbach
- National High Magnetic Field Laboratory, Florida State University, Tallahassee, Florida 32310-3706, USA
| | - Y F Hu
- Beijing National Laboratory for Molecular Sciences, State Key Laboratory of Rare Earth Materials Chemistry and Applications, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, People's Republic of China
| | - Y X Wang
- Beijing National Laboratory for Molecular Sciences, State Key Laboratory of Rare Earth Materials Chemistry and Applications, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, People's Republic of China
| | - E S Choi
- National High Magnetic Field Laboratory, Florida State University, Tallahassee, Florida 32310-3706, USA
| | - B S Shastry
- Department of Physics, University of California, Santa Cruz, California 95064, USA
| | - A P Ramirez
- Department of Physics, University of California, Santa Cruz, California 95064, USA
| | - H D Zhou
- Department of Physics and Astronomy, University of Tennessee, Knoxville, Tennessee 37996-1200, USA
- National High Magnetic Field Laboratory, Florida State University, Tallahassee, Florida 32310-3706, USA
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24
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Ma J, Kamiya Y, Hong T, Cao HB, Ehlers G, Tian W, Batista CD, Dun ZL, Zhou HD, Matsuda M. Static and Dynamical Properties of the Spin-1/2 Equilateral Triangular-Lattice Antiferromagnet Ba_{3}CoSb_{2}O_{9}. Phys Rev Lett 2016; 116:087201. [PMID: 26967439 DOI: 10.1103/physrevlett.116.087201] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/18/2015] [Indexed: 06/05/2023]
Abstract
We present single-crystal neutron scattering measurements of the spin-1/2 equilateral triangular-lattice antiferromagnet Ba_{3}CoSb_{2}O_{9}. Besides confirming that the Co^{2+} magnetic moments lie in the ab plane for zero magnetic field and then determining all the exchange parameters of the minimal quasi-2D spin Hamiltonian, we provide conclusive experimental evidence of magnon decay through observation of intrinsic line broadening. Through detailed comparisons with the linear and nonlinear spin-wave theories, we also point out that the large-S approximation, which is conventionally employed to predict magnon decay in noncollinear magnets, is inadequate to explain our experimental observation. Thus, our results call for a new theoretical framework for describing excitation spectra in low-dimensional frustrated magnets under strong quantum effects.
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Affiliation(s)
- J Ma
- Department of Physics and Astronomy, University of Tennessee, Knoxville, Tennessee 37996, USA
- Quantum Condensed Matter Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - Y Kamiya
- iTHES Research Group and Condensed Matter Theory Laboratory, RIKEN, Wako, Saitama 351-0198, Japan
| | - Tao Hong
- Quantum Condensed Matter Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - H B Cao
- Quantum Condensed Matter Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - G Ehlers
- Quantum Condensed Matter Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - W Tian
- Quantum Condensed Matter Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - C D Batista
- Theoretical Division, T-4 and CNLS, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - Z L Dun
- Department of Physics and Astronomy, University of Tennessee, Knoxville, Tennessee 37996, USA
| | - H D Zhou
- Department of Physics and Astronomy, University of Tennessee, Knoxville, Tennessee 37996, USA
- National High Magnetic Field Laboratory, Florida State University, Tallahassee, Florida 32310-3706, USA
| | - M Matsuda
- Quantum Condensed Matter Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
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25
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Hoch MJR, Zhou HD, Mun E, Harrison N. Pulsed field magnetization in rare-earth kagome systems. J Phys Condens Matter 2016; 28:046001. [PMID: 26732305 DOI: 10.1088/0953-8984/28/4/046001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
The rare-earth kagome systems R 3Ga5SiO14 (R = Nd or Pr) exhibit cooperative paramagnetism at low temperatures. Evidence for correlated spin clusters in these weakly frustrated systems has previously been obtained from neutron scattering and from ESR and NMR results. The present pulsed field (0-60 T, 25 ms) magnetization measurements made on single crystals of Nd3Ga5SiO14 (NGS) and Pr3Ga5SiO14 (PGS) at temperatures down to 450 mK have revealed striking differences in the magnetic responses of the two materials. For NGS the magnetization shows a low field plateau, saturation in high transient fields, and significant hysteresis while the PGS magnetization does not saturate in transient fields up to 60 T and shows no hysteresis or plateaus. Nd(3+) is a Kramers ion while Pr(3+) is a non-Kramers ion and the crystal field effects are quite different in the two systems. For the conditions used in the experiments the magnetization behavior is not in agreement with Heisenberg model predictions for kagome systems in which easy-axis anisotropy is much larger than the exchange coupling. The extremely slow spin dynamics found below 4 K in NGS is, however, consistent with the model for Kramers ions and provides a basis for explaining the pulsed field magnetization features.
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Affiliation(s)
- M J R Hoch
- National High Magnetic Field Laboratory, Florida State University, Tallahassee, FL 32310, USA
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26
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Hallas AM, Cheng JG, Arevalo-Lopez AM, Silverstein HJ, Su Y, Sarte PM, Zhou HD, Choi ES, Attfield JP, Luke GM, Wiebe CR. Incipient ferromagnetism in Tb2Ge2O7: application of chemical pressure to the enigmatic spin-liquid compound Tb2Ti2O7. Phys Rev Lett 2014; 113:267205. [PMID: 25615381 DOI: 10.1103/physrevlett.113.267205] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/24/2014] [Indexed: 06/04/2023]
Abstract
After nearly 20 years of study, the origin of the spin-liquid state in Tb2Ti2O7 remains a challenge for experimentalists and theorists alike. To improve our understanding of the exotic magnetism in Tb2Ti2O7, we synthesize a chemical pressure analog: Tb2Ge2O7. Substitution of titanium by germanium results in a lattice contraction and enhanced exchange interactions. We characterize the magnetic ground state of Tb2Ge2O7 with specific heat, ac and dc magnetic susceptibility, and polarized neutron scattering measurements. Akin to Tb2Ti2O7, there is no long-range order in Tb2Ge2O7 down to 20 mK. The Weiss temperature of -19.2(1) K, which is more negative than that of Tb2Ti2O7, supports the picture of stronger antiferromagnetic exchange. Polarized neutron scattering of Tb2Ge2O7 reveals that liquidlike correlations dominate in this system at 3.5 K. However, below 1 K, the liquidlike correlations give way to intense short-range ferromagnetic correlations with a length scale similar to the Tb-Tb nearest neighbor distance. Despite stronger antiferromagnetic exchange, the ground state of Tb2Ge2O7 has ferromagnetic character, in stark contrast to the pressure-induced antiferromagnetic order observed in Tb2Ti2O7.
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Affiliation(s)
- A M Hallas
- Department of Physics and Astronomy, McMaster University, Hamilton, Ontario L8S 4M1, Canada
| | - J G Cheng
- Beijing National Laboratory for Condensed Matter Physics, and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
| | - A M Arevalo-Lopez
- Centre for Science at Extreme Conditions and School of Chemistry, University of Edinburgh, King's Buildings, Mayfield Road, Edinburgh EH9 3JZ, United Kingdom
| | - H J Silverstein
- Department of Chemistry, University of Manitoba, Winnipeg, Manitoba R3T 2N2, Canada
| | - Y Su
- Jülich Centre for Neutron Science, Forschungszentrum Jülich GmbH, Outstation at MLZ, Lichtenbergstrasse 1, 85747 Garching, Germany
| | - P M Sarte
- Department of Chemistry, University of Manitoba, Winnipeg, Manitoba R3T 2N2, Canada
| | - H D Zhou
- Department of Physics and Astronomy, University of Tennessee, Knoxville, Tennessee 37996-1200, USA and National High Magnetic Field Laboratory, Florida State University, Tallahassee, Florida 32306-4005, USA
| | - E S Choi
- National High Magnetic Field Laboratory, Florida State University, Tallahassee, Florida 32306-4005, USA
| | - J P Attfield
- Centre for Science at Extreme Conditions and School of Chemistry, University of Edinburgh, King's Buildings, Mayfield Road, Edinburgh EH9 3JZ, United Kingdom
| | - G M Luke
- Department of Physics and Astronomy, McMaster University, Hamilton, Ontario L8S 4M1, Canada and Canadian Institute for Advanced Research, Toronto, Ontario M5G 1Z7, Canada
| | - C R Wiebe
- Department of Physics and Astronomy, McMaster University, Hamilton, Ontario L8S 4M1, Canada and Department of Chemistry, University of Manitoba, Winnipeg, Manitoba R3T 2N2, Canada and Department of Chemistry, University of Winnipeg, Winnipeg, Manitoba R3B 2E9, Canada
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27
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Zhu M, Do D, Dela Cruz CR, Dun Z, Zhou HD, Mahanti SD, Ke X. Tuning the magnetic exchange via a control of orbital hybridization in Cr(2)(Te(1-x)W(x))O(6). Phys Rev Lett 2014; 113:076406. [PMID: 25170719 DOI: 10.1103/physrevlett.113.076406] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/03/2014] [Indexed: 06/03/2023]
Abstract
We report the complex magnetic phase diagram and electronic structure of Cr_{2}(Te_{1-x}W_{x})O_{6} systems. While compounds with different x values possess the same crystal structure, they display different magnetic structures below and above x_{c}=0.7, where both the transition temperature T_{N} and sublattice magnetization (M_{s}) reach a minimum. Unlike many known cases where magnetic interactions are controlled either by injection of charge carriers or by structural distortion induced via chemical doping, in the present case it is achieved by tuning the orbital hybridization between Cr 3d and O 2p orbitals through W 5d states. The result is supported by ab initio electronic structure calculations. Through this concept, we introduce a new approach to tune magnetic and electronic properties via chemical doping.
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Affiliation(s)
- M Zhu
- Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824, USA
| | - D Do
- Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824, USA
| | - C R Dela Cruz
- Quantum Condensed Matter Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - Z Dun
- Department of Physics and Astronomy, University of Tennessee, Knoxville, Tennessee 37996, USA
| | - H D Zhou
- Department of Physics and Astronomy, University of Tennessee, Knoxville, Tennessee 37996, USA and National High Magnetic Field Laboratory, Florida State University, Tallahassee, Florida 32306, USA
| | - S D Mahanti
- Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824, USA
| | - X Ke
- Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824, USA
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28
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Mun ED, Chern GW, Pardo V, Rivadulla F, Sinclair R, Zhou HD, Zapf VS, Batista CD. Magnetic field induced transition in vanadium spinels. Phys Rev Lett 2014; 112:017207. [PMID: 24483929 DOI: 10.1103/physrevlett.112.017207] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/16/2013] [Indexed: 06/03/2023]
Abstract
We study vanadium spinels AV2O4 (A = Cd,Mg) in pulsed magnetic fields up to 65 T. A jump in magnetization at μ0H≈40 T is observed in the single-crystal MgV2O4, indicating a field induced quantum phase transition between two distinct magnetic orders. In the multiferroic CdV2O4, the field induced transition is accompanied by a suppression of the electric polarization. By modeling the magnetic properties in the presence of strong spin-orbit coupling characteristic of vanadium spinels, we show that both features of the field induced transition can be successfully explained by including the effects of the local trigonal crystal field.
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Affiliation(s)
- E D Mun
- NHMFL Materials Physics and Applications, T-4 and CNLS, Los Alamos Laboratory (LANL), Los Alamos, New Mexico 87545, USA
| | - Gia-Wei Chern
- Theoretical Division, T-4 and CNLS, Los Alamos Laboratory, Los Alamos, New Mexico 87545, USA
| | - V Pardo
- Departamento de Fisica Aplicada, Universidad de Santiago de Compostela, 15782 Santiago de Compostela, Spain
| | - F Rivadulla
- CIQUS, Universidad de Santiago de Compostela, 15782 Santiago de Compostela, Spain
| | - R Sinclair
- Department of Physics and Astronomy, University of Tennessee, Knoxville, Tennessee 37996-1200, USA
| | - H D Zhou
- Department of Physics and Astronomy, University of Tennessee, Knoxville, Tennessee 37996-1200, USA
| | - V S Zapf
- NHMFL Materials Physics and Applications, T-4 and CNLS, Los Alamos Laboratory (LANL), Los Alamos, New Mexico 87545, USA
| | - C D Batista
- Theoretical Division, T-4 and CNLS, Los Alamos Laboratory, Los Alamos, New Mexico 87545, USA
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29
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Cheng JG, Zhou JS, Yang YF, Zhou HD, Matsubayashi K, Uwatoko Y, MacDonald A, Goodenough JB. Possible Kondo physics near a metal-insulator crossover in the a-site ordered perovskite CaCu3Ir4O12. Phys Rev Lett 2013; 111:176403. [PMID: 24206506 DOI: 10.1103/physrevlett.111.176403] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/03/2013] [Revised: 09/05/2013] [Indexed: 06/02/2023]
Abstract
The A-site ordered perovskite (AA(3)')B(4)O(12) can accommodate transition metals on both A' and B sites in the crystal structure. Because of this structural feature, it is possible to have narrow-band electrons interacting with broadband electrons from different sublattices. Here we report a new A-site ordered perovskite (CaCu(3))Ir(4)O(12) synthesized under high pressure. The coupling between localized spins on Cu(2+) and itinerant electrons from the Ir-O sublattice makes Kondo-like physics take place at a temperature as high as 80 K. Results from the local density approximation calculation have confirmed the relevant band structure. The magnetization anomaly found at 80 K can be well rationalized by the two-fluid model.
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Affiliation(s)
- J-G Cheng
- Materials Science and Engineering Program and Texas Materials Institute, University of Texas at Austin, Austin, Texas 78712, USA and Institute for Solid State Physics, University of Tokyo, Kashiwa 277-8581, Japan and Beijing National Laboratory for Condensed Matter Physics, and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
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30
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Silverstein HJ, Sharma AZ, Stoller AJ, Cruz-Kan K, Flacau R, Donaberger RL, Zhou HD, Manuel P, Huq A, Kolesnikov AI, Wiebe CR. Phase diagram and magnetic structures of the Co-bearing dugganites Pb3TeCo3A2O14 (A = V, P). J Phys Condens Matter 2013; 25:246004. [PMID: 23707984 DOI: 10.1088/0953-8984/25/24/246004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Exhibiting rich magnetic behaviour and potentially multiferroic properties, the dugganites, a Te(6+) containing subgroup of the langasite series, are an attractive family of compounds for future study. It was recently shown that Pb-bearing members of the dugganite series undergo distortions away from the P321 symmetry that is characteristic of the langasites. Here, we detail the consequences these distortions have on the magnetism exhibited by Pb3TeCo3V2O14 and Pb3TeCo3P2O14, solving the magnetic structures of both compounds with respect to a new supercell. Using neutron scattering and magnetic susceptibility measurements, we show that small applied magnetic fields can seriously perturb the delicate magnetic states in both of these systems. This is further demonstrated by presenting how doping P(5+) onto the nonmagnetic V(5+) site completely changes the magnetic structure from either of the end series members. Finally, it is shown using inelastic neutron scattering and magnetic susceptibility measurements that Pb3TeCo3V2O14 can be characterized using a model for isosceles trimers, which do not exist in the previously reported P321 subcell.
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Affiliation(s)
- H J Silverstein
- Department of Chemistry, University of Manitoba, Winnipeg, MB, Canada.
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Zhou HD, Xu C, Hallas AM, Silverstein HJ, Wiebe CR, Umegaki I, Yan JQ, Murphy TP, Park JH, Qiu Y, Copley JRD, Gardner JS, Takano Y. Successive phase transitions and extended spin-excitation continuum in the S=1/2 triangular-lattice antiferromagnet Ba3CoSb2O9. Phys Rev Lett 2012; 109:267206. [PMID: 23368612 DOI: 10.1103/physrevlett.109.267206] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2012] [Indexed: 06/01/2023]
Abstract
Using magnetic, thermal, and neutron measurements on single-crystal samples, we show that Ba3CoSb2O9 is a spin-1/2 triangular-lattice antiferromagnet with the c axis as the magnetic easy axis and two magnetic phase transitions bracketing an intermediate up-up-down phase in magnetic field applied along the c axis. A pronounced extensive neutron-scattering continuum above spin-wave excitations, observed below T(N), implies that the system is in close proximity to one of two spin-liquid states that have been predicted for a 2D triangular lattice.
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Affiliation(s)
- H D Zhou
- Department of Physics and Astronomy, University of Tennessee, Knoxville, Tennessee 37996-1200, USA.
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Hwang J, Choi ES, Ye F, Dela Cruz CR, Xin Y, Zhou HD, Schlottmann P. Successive magnetic phase transitions and multiferroicity in the spin-one triangular-lattice antiferromagnet Ba3NiNb2O9. Phys Rev Lett 2012; 109:257205. [PMID: 23368494 DOI: 10.1103/physrevlett.109.257205] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/03/2012] [Revised: 09/12/2012] [Indexed: 06/01/2023]
Abstract
We report the magnetic and electric properties of Ba3NiNb2O9, which is a quasi-two-dimensional spin-one triangular-lattice antiferromagnet with trigonal structure. At low T and with increasing magnetic field, the system evolves from a 120 degree magnetic ordering phase (A phase) to an up-up-down (uud) phase (B phase) with a change of slope at 1/3 of the saturation magnetization, and then to an "oblique" phase (C phase). Accordingly, the ferroelectricity switches on at each phase boundary with appearance of spontaneous polarization. Therefore, Ba3NiNb2O9 is a unique triangular-lattice antiferromagnet exhibiting both uud phase and multiferroicity.
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Affiliation(s)
- J Hwang
- National High Magnetic Field Laboratory, Florida State University, Tallahassee, Florida 32310-3706, USA
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Xin Y, Zhou HD, Cheng JG, Zhou JS, Goodenough JB. Study of atomic structure and electronic structure of an AA'3B4O12 double-perovskite CaCu3Ir4O12 using STEM imaging and EELS techniques. Ultramicroscopy 2012; 127:94-9. [PMID: 22951264 DOI: 10.1016/j.ultramic.2012.07.019] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
A newly discovered 1:3 A-site-ordered AA'3B4O12 perovskite oxide CaCu3Ir4O12 which has unusual electrical and magnetic properties was investigated using STEM imaging and EELS techniques in a probe corrected microscope. The target sample was compared with the other two iso-structural oxides of CaCu3Ru4O12 and CaCu3Ti4O12 with dissimilar physical properties. It has been found by STEM HAADF imaging that Ca and Cu on A and A' sites are ordered as expected. Oxygen atoms are imaged with STEM ABF imaging. The fine structures of the Cu L2,3 core loss and O-K edges show that the electronic structure of CaCu3Ir4O12 is very close to that of CaCu3Ru4O12, but different from CaCu3Ti4O12. The O-K near edge fine structures show extensive hybridization of Ir 5d and O 2p band. Cu L2,3 peaks indicate Cu in CaCu3Ir4O12 has 2+ valence, though Cu(2+) electrons mainly localized, they might have strong interactions with Ir(4+) 5d electrons through Ir-O-Cu, similar to the strong coupling of Ru with Cu in CaCu3Ru4O12.
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Affiliation(s)
- Y Xin
- National High Magnetic Field Laboratory, Florida State University, Tallahassee, FL 32310, USA.
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34
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Choi KY, Wang Z, Ozarowski A, van Tol J, Zhou HD, Wiebe CR, Skourski Y, Dalal NS. Spin dynamics of the S = 5/2 2D triangular antiferromagnet Ba3NbFe3Si2O14. J Phys Condens Matter 2012; 24:246001. [PMID: 22627202 DOI: 10.1088/0953-8984/24/24/246001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
We report pulse-field magnetization, ac susceptibility, and 100 GHz electron spin resonance (ESR) measurements on the S = 5/2 two-dimensional triangular compound Ba3NbFe3Si2O14 with the Néel temperature T(N) = 26 K. The magnetization curve shows an almost linear increase up to 60 T with no indication of a one-third magnetization plateau. An unusually large frequency dependence of the ac susceptibility in the temperature range of T = 20-100 K reveals a spin-glass behavior or superparamagnetism, signaling the presence of frustration-related slow magnetic fluctuations. The temperature dependence of the ESR linewidth exhibits two distinct critical regimes; (i) ΔH(pp)(T) is proportional to (T-T(N))(-p) with the exponent p = 0.2(1)-0.2(3) for temperatures above 27 K, and (ii) ΔH(pp)(T) is proportional to (T-T*)(-p) with T* = 12 K and p = 0.8(1)-0.8(4) for temperatures between 12 and 27 K. This is interpreted as indicating a dimensional crossover of magnetic interactions and the persistence of short-range correlations with a helically ordered state.
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Affiliation(s)
- K Y Choi
- Department of Physics, Chung-Ang University, Seoul, Republic of Korea.
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35
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Cheng JG, Zhou JS, Goodenough JB, Zhou HD, Matsubayashi K, Uwatoko Y, Kong PP, Jin CQ, Yang WG, Shen GY. Pressure effect on the structural transition and suppression of the high-spin state in the triple-layer T'-La4Ni3O8. Phys Rev Lett 2012; 108:236403. [PMID: 23003979 DOI: 10.1103/physrevlett.108.236403] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/02/2012] [Indexed: 06/01/2023]
Abstract
We report a comprehensive high-pressure study on the triple-layer T'-La4Ni3O8 with a suite of experimental probes, including structure determination, magnetic, and transport properties up to 50 GPa. Consistent with a recent ab inito calculation, application of hydrostatic pressure suppresses an insulator-metal spin-state transition at P(c)≈6 GPa. However, a low-spin metallic phase does not emerge after the high-spin state is suppressed to the lowest temperature. For P>20 GPa, the ambient T' structure transforms gradually to a T(†)-type structure, which involves a structural reconstruction from fluorite La-O2-La blocks under low pressures to rock-salt LaO-LaO blocks under high pressures. Absence of the metallic phase under pressure has been discussed in terms of local displacements of O2- ions in the fluorite block under pressure before a global T(†) phase is established.
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Affiliation(s)
- J-G Cheng
- Materials Science and Engineering Program/Mechanical Engineering, University of Texas at Austin, Austin, Texas 78712, USA
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36
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Zhou HD, Cheng JG, Hallas AM, Wiebe CR, Li G, Balicas L, Zhou JS, Goodenough JB, Gardner JS, Choi ES. Chemical pressure effects on pyrochlore spin ice. Phys Rev Lett 2012; 108:207206. [PMID: 23003185 DOI: 10.1103/physrevlett.108.207206] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2012] [Indexed: 06/01/2023]
Abstract
A comparison among the two sets of studied pyrochlore spin ices, Ho2Sn2O7, Ho2Ti2O7, and Ho2Ge2O7 with Ho3+ spins and Dy2Sn2O7, Dy2Ti2O7, and Dy2Ge2O7 with Dy3+ spins, shows that the application of chemical pressure through each set drives the system toward the antiferromagnetic phase boundary from the spin ice region, which agrees with the prediction of the "dipolar spin ice" model of den Hertog and Gingras. Among all the studied pyrochlore spin ices, Dy2Ge2O7 has the smallest ratio of Jnn/Dnn=-0.73.
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Affiliation(s)
- H D Zhou
- National High Magnetic Field Laboratory, Florida State University, Tallahassee, Florida 32306-4005, USA
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37
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Cheng JG, Li G, Balicas L, Zhou JS, Goodenough JB, Xu C, Zhou HD. High-pressure sequence of Ba3NiSb2O9 structural phases: new S = 1 quantum spin liquids based on Ni2+. Phys Rev Lett 2011; 107:197204. [PMID: 22181641 DOI: 10.1103/physrevlett.107.197204] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/2011] [Indexed: 05/31/2023]
Abstract
Two new gapless quantum spin-liquid candidates with S = 1 (Ni(2+)) moments: the 6H-B phase of Ba(3)NiSb(2)O(9) with a Ni(2+)-triangular lattice and the 3C phase with a Ni(2/3)Sb(1/3)-three-dimensional edge-shared tetrahedral lattice were obtained under high pressure. Both compounds show no magnetic order down to 0.35 K despite Curie-Weiss temperatures θ(CW) of -75.5 (6H-B) and -182.5 K (3C), respectively. Below ~25 K, the magnetic susceptibility of the 6H-B phase saturates to a constant value χ(0) = 0.013 emu/mol, which is followed below 7 K by a linear-temperature-dependent magnetic specific heat (C(M)) displaying a giant coefficient γ = 168 mJ/mol K(2). Both observations suggest the development of a Fermi-liquid-like ground state. For the 3C phase, the C(M) perpendicular T(2) behavior indicates a unique S = 1, 3D quantum spin-liquid ground state.
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Affiliation(s)
- J G Cheng
- Texas Materials Institute, University of Texas at Austin, Texas 78712, USA
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Kovnir K, Garlea VO, Thompson CM, Zhou HD, Reiff WM, Ozarowski A, Shatruk M. Spin-glass behavior in LaFe(x)Co(2-x)P2 solid solutions: interplay between magnetic properties and crystal and electronic structures. Inorg Chem 2011; 50:10274-83. [PMID: 21919479 DOI: 10.1021/ic201328y] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
To explore the evolution of magnetic properties from ferromagnetic LaCo(2)P(2) to paramagnetic LaFe(2)P(2) (both of ThCr(2)Si(2) structure type) a series of mixed composition LaFe(x)Co(2-x)P(2) (x ≤ 0.5) has been comprehensively investigated by means of single-crystal and powder X-ray and neutron diffraction, magnetization and heat capacity measurements, Mössbauer spectroscopy, and electronic band structure calculations. The Curie temperature decreases from 132 K in LaCo(2)P(2) to 91 K in LaFe(0.05)Co(1.95)P(2). The ferromagnetic ordering is suppressed at higher Fe content. LaFe(0.1)Co(1.9)P(2) and LaFe(0.2)Co(1.8)P(2) demonstrate spin-glass-like behavior, which was also confirmed by the absence of characteristic features of long-range magnetic ordering, namely, a λ-type anomaly in the heat capacity, a hyperfine splitting in the Mössbauer spectrum, and magnetic reflections in the neutron diffraction pattern. Finally, both LaFe(0.3)Co(1.7)P(2) and LaFe(0.5)Co(1.5)P(2) exhibit paramagnetic behavior down to 1.8 K. The unit cell parameters of the mixed compounds do not follow the Vegard behavior as the increase in the Fe content results in the decrease of average M-M distances (M = Fe, Co). Quantum-chemical calculations and crystal orbital Hamiltonian population analysis reveal that upon aliovalent (nonisoelectronic) substitution of Fe for Co the antibonding character of M-M interactions is reduced while the Fermi level is shifted below the DOS peak in the 3d metal subband. As the result, at higher Fe content the Stoner criterion is not satisfied and no magnetic ordering is observed.
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Affiliation(s)
- Kirill Kovnir
- Department of Chemistry and Biochemistry, Florida State University, Tallahassee, Florida 32306, USA
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39
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Sarte PM, Silverstein HJ, Van Wyk BTK, Gardner JS, Qiu Y, Zhou HD, Wiebe CR. Absence of long-range magnetic ordering in the pyrochlore compound Er2Sn2O7. J Phys Condens Matter 2011; 23:382201. [PMID: 21891830 DOI: 10.1088/0953-8984/23/38/382201] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The low temperature behaviour of powder Er2Sn2O7 samples has been studied by magnetic susceptibility, heat capacity, and neutron scattering experiments. We report here the absence of magnetic ordering down to 100 mK. Anomalies in the heat capacity can be accounted for through an analysis of the crystal field spectrum observed by inelastic neutron scattering spectroscopy. These new measurements on Er2Sn2O7 suggest a new lower bound for the frustration index of f = |Θ(CW)|/T(N) = 14/0.1 = 140, placing this compound into a highly frustrated regime.
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Affiliation(s)
- P M Sarte
- Department of Chemistry, University of Winnipeg, Winnipeg, MB, R3B 2E9, Canada
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Zhou HD, Bramwell ST, Cheng JG, Wiebe CR, Li G, Balicas L, Bloxsom JA, Silverstein HJ, Zhou JS, Goodenough JB, Gardner JS. High pressure route to generate magnetic monopole dimers in spin ice. Nat Commun 2011; 2:478. [PMID: 21934662 PMCID: PMC3195216 DOI: 10.1038/ncomms1483] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2011] [Accepted: 08/17/2011] [Indexed: 11/09/2022] Open
Abstract
The gas of magnetic monopoles in spin ice is governed by one key parameter: the monopole chemical potential. A significant variation of this parameter could access hitherto undiscovered magnetic phenomena arising from monopole correlations, as observed in the analogous electrical Coulomb gas, like monopole dimerization, critical phase separation, or charge ordering. However, all known spin ices have values of chemical potential imposed by their structure and chemistry that place them deeply within the weakly correlated regime, where none of these interesting phenomena occur. Here we use high-pressure synthesis to create a new monopole host, Dy(2)Ge(2)O(7), with a radically altered chemical potential that stabilizes a large fraction of monopole dimers. The system is found to be ideally described by the classic Debye-Huckel-Bjerrum theory of charge correlations. We thus show how to tune the monopole chemical potential in spin ice and how to access the diverse collective properties of magnetic monopoles.
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Affiliation(s)
- H D Zhou
- National High Magnetic Field Laboratory, Florida State University, Tallahassee, USA
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41
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Ghosh S, Zhou HD, Balicas L, Hill S, Gardner JS, Qiu Y, Wiebe CR. Short range ordering in the modified honeycomb lattice compound SrHo(2)O(4). J Phys Condens Matter 2011; 23:164203. [PMID: 21471622 DOI: 10.1088/0953-8984/23/16/164203] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
The low temperature behaviour of single crystalline SrHo(2)O(4) has been characterized by dc magnetic susceptibility, heat capacity, and neutron scattering experiments. Our results show that despite the lack of magnetic long-ranged ordering in the presence of strong antiferromagnetic correlations, SrHo(2)O(4) does not order down to 1.8 K. Elastic neutron scattering experiments show prominent magnetic diffuse scattering correlated with a broad feature in the dc susceptibility at T = 4 K, indicative of magnetic short-ranged ordering of the Ho(3) spins. Inelastic neutron scattering shows the presence of five crystal field levels up to 80 K in energy, in agreement with the integration of the magnetic specific heat component yielding Rln5 entropy release. The magnetic short-ranged ordering is fitted to a nearest neighbour interaction model with good agreement.
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Affiliation(s)
- S Ghosh
- Department of Physics, Florida State University, Tallahassee, FL 32306, USA
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Li J, Wang YJ, Zhang M, Xu ZQ, Gao CY, Fang CQ, Yan JC, Zhou HD. Vascular risk factors promote conversion from mild cognitive impairment to Alzheimer disease. Neurology 2011; 76:1485-91. [PMID: 21490316 DOI: 10.1212/wnl.0b013e318217e7a4] [Citation(s) in RCA: 248] [Impact Index Per Article: 19.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
OBJECTIVE Growing evidence suggests that vascular risk factors (VRF) contribute to cognitive decline. The aim of this study was to investigate the impact of VRF on the conversion from mild cognitive impairment (MCI) to Alzheimer disease (AD) dementia. METHODS A total of 837 subjects with MCI were enrolled at baseline and followed up annually for 5 years. The incidence of AD dementia was investigated. A mixed random effects regression model was used to analyze the association between VRF and the progression of MCI assessed with Mini-Mental State Examination and instrumental Activities of Daily Living. Cox proportional hazard models were used to identify the association between VRF and dementia conversion, and to examine whether treatment of VRF can prevent dementia conversion. RESULTS At the end of the follow-up, 298 subjects converted to AD dementia, while 352 remained MCI. Subjects with VRF had a faster progression in cognition and function relative to subjects without. VRF including hypertension, diabetes, cerebrovascular diseases, and hypercholesterolemia increased the risk of dementia conversion. Those subjects with MCI in whom all VRF were treated had a lower risk of dementia than those who had some VRF treated. Treatment of individual VRF including hypertension, diabetes, and hypercholesterolemia was associated with the reduced risk of AD conversion. CONCLUSION VRF increased the risk of incident AD dementia. Treatment of VRF was associated with a reduced risk of incident AD dementia. Although our findings are observational, they suggest active intervention for VRF might reduce progression in MCI to AD dementia.
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Affiliation(s)
- J Li
- Department of Neurology and Center for Clinical Neuroscience, Daping Hospital, No. 10 Changjiang Branch Road, Daping, Chongqing, China
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Zhou HD, Choi ES, Li G, Balicas L, Wiebe CR, Qiu Y, Copley JRD, Gardner JS. Spin liquid state in the S = 1/2 triangular lattice Ba3CuSb2O9. Phys Rev Lett 2011; 106:147204. [PMID: 21561219 DOI: 10.1103/physrevlett.106.147204] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/12/2010] [Indexed: 05/30/2023]
Abstract
The synthesis and characterization of Ba3CuSb2O9, which has a layered array of Cu2+ spins in a triangular lattice, are reported. The magnetic susceptibility and neutron scattering experiments of this material show no magnetic ordering down to 0.2 K with a θ(CW) = -55 K. The magnetic specific heat reveals a T-linear dependence with a γ = 43.4 mJ K(-2) mol(-1) below 1.4 K. These observations suggest that Ba3CuSb2O9 is a new quantum spin liquid candidate with a S = 1/2 triangular lattice.
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Affiliation(s)
- H D Zhou
- National High Magnetic Field Laboratory, Florida State University, Tallahassee, Florida 32306-4005, USA.
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Kismarahardja A, Brooks JS, Kiswandhi A, Matsubayashi K, Yamanaka R, Uwatoko Y, Whalen J, Siegrist T, Zhou HD. Co[V2]o4: a spinel approaching the itinerant electron limit. Phys Rev Lett 2011; 106:056602. [PMID: 21405419 DOI: 10.1103/physrevlett.106.056602] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/29/2010] [Indexed: 05/30/2023]
Abstract
Studies of the structure, magnetization, and resistivity under pressure on stoichiometric normal spinel Co[V(2)]O(4) single crystals show (i) absence of a structural distortion, (ii) abnormal magnetic critical exponents, and (iii) metallic conductivity induced by pressures at low temperatures. All these results prove that Co[V(2)]O(4) sits on the edge of the itinerant-electron limit. Compared with similar measurements on Fe[V(2)]O(4) and other A[V(2)]O(4) studies, it is shown that a critical V-V separation for a localized-itinerant electronic phase transition exists.
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Affiliation(s)
- A Kismarahardja
- National High Magnetic Field Laboratory, Florida State University, Tallahassee, Florida 32306-4005, USA
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45
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Xu XS, Brinzari TV, McGill S, Zhou HD, Wiebe CR, Musfeldt JL. Absence of spin liquid behavior in Nd3Ga5SiO14 using magneto-optical spectroscopy. Phys Rev Lett 2009; 103:267402. [PMID: 20366345 DOI: 10.1103/physrevlett.103.267402] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2009] [Indexed: 05/29/2023]
Abstract
We measured the low-lying crystal field levels of Nd3+ in Nd3Ga5SiO14 via magneto-optical spectroscopy and employed the extracted energies, magnetic moments, and symmetries to analyze the magnetic properties and test the spin liquid candidacy of this material. The exchange interaction is surprisingly small, a discovery that places severe constraints on models used to describe the ground state of this system. Further, it demonstrates the value of local-probe photophysical techniques for rare-earth-containing materials where bulk property measurements can be skewed by low-lying electronic structure.
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Affiliation(s)
- X S Xu
- Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996, USA
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Janik JA, Zhou HD, Jo YJ, Balicas L, Macdougall GJ, Luke GM, Garrett JD, McClellan KJ, Bauer ED, Sarrao JL, Qiu Y, Copley JRD, Yamani Z, Buyers WJL, Wiebe CR. Itinerant spin excitations near the hidden order transition in URu(2)Si(2). J Phys Condens Matter 2009; 21:192202. [PMID: 21825472 DOI: 10.1088/0953-8984/21/19/192202] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
By means of neutron scattering we show that the high temperature precursor to the hidden order state of the heavy fermion superconductor URu(2)Si(2) exhibits heavily damped incommensurate paramagnons whose strong energy dispersion is very similar to that of the long-lived longitudinal f spin excitations that appear below T(0). This suggests that there is a strongly hybridized character to the itinerant excitations observed previously above the hidden order transition. Here we present evidence that the itinerant excitations, like those in chromium, are due to Fermi surface nesting of hole and electron pockets; hence the hidden order phase probably originates from a Fermi surface instability. We identify wavevectors that span nested regions of a f-d hybridized band calculation and that match the neutron spin crossover from incommensurate to commensurate on approach to the hidden order phase.
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Affiliation(s)
- J A Janik
- Department of Physics, Florida State University, Tallahassee, FL 32306-3016, USA. National High Magnetic Field Laboratory, Florida State University, Tallahassee, FL 32306-4005, USA
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47
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Zhou HD, Wiebe CR, Jo YJ, Balicas L, Urbano RR, Lumata LL, Brooks JS, Kuhns PL, Reyes AP, Qiu Y, Copley JRD, Gardner JS. Chemical pressure induced spin freezing phase transition in kagome pr langasites. Phys Rev Lett 2009; 102:067203. [PMID: 19257628 DOI: 10.1103/physrevlett.102.067203] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/15/2008] [Revised: 12/12/2008] [Indexed: 05/27/2023]
Abstract
The 2D kagome system Pr3Ga5SiO14 has been previously identified as a spin-liquid candidate in zero field, displaying no magnetic long-ranged order down to at least 35 mK. Perturbations upon such systems, either under applied fields or applied pressure, should induce a spin freezing phase transition, but there are very few experimental realizations of this phenomena other than the well-studied 3D pyrochlore Tb2Ti2O7. In this Letter, we report the observation of a spin freezing phase transition in Pr3Ga5SiO14 through the application of chemical pressure--that is, through a systematic substitution on the Si site with larger ions and an elongation of the nearest-neighbor Pr-Pr distance in the kagome lattice. This results in a suppression of the T2 component of the heat capacity, and the reduction of the exchange constant eventually leads to dipolar-driven spin freezing.
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Affiliation(s)
- H D Zhou
- Department of Physics, Florida State University, Tallahassee, Florida 32306-3016, USA
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Giblin SR, Champion JDM, Zhou HD, Wiebe CR, Gardner JS, Terry I, Calder S, Fennell T, Bramwell ST. Static magnetic order in Tb2Sn2O7 revealed by muon spin relaxation with exterior muon implantation. Phys Rev Lett 2008; 101:237201. [PMID: 19113586 DOI: 10.1103/physrevlett.101.237201] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/16/2008] [Revised: 10/16/2008] [Indexed: 05/27/2023]
Abstract
Tb2Sn2O7 has been proposed as an ordered spin ice, but the precise nature of the low temperature magnetic state remains uncertain. Recent independent muon spin relaxation (microSR) investigations suggest the possibility of exotic ground states with static order precluded on time scales longer than 10(-6) s. Here the more conventional hypothesis of canted ferromagnetism is tested by means of microSR with the muons stopped outside the sample, as well as ultralow field bulk magnetization measurements. The field cooled state shows conventional static order, while the zero field cooled state may be interpreted in terms of conventional closed domains. These results rule out purely dynamical ground states and illustrate the value of exterior muon implantation as a complement to the conventional technique.
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Affiliation(s)
- S R Giblin
- ISIS Facility, Rutherford Appleton Laboratory, Chilton, Didcot, Oxon, OX11 0QX, United Kingdom.
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Zhou HD, Wiebe CR, Janik JA, Balicas L, Yo YJ, Qiu Y, Copley JRD, Gardner JS. Dynamic spin ice: Pr2Sn2O7. Phys Rev Lett 2008; 101:227204. [PMID: 19113519 DOI: 10.1103/physrevlett.101.227204] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/13/2008] [Indexed: 05/27/2023]
Abstract
In this Letter, we report a new spin ice--Pr2Sn2O7--which appears to have enhanced residual entropy due to the dynamic nature of the spins. Neutron scattering experiments show that at 200 mK, there is a significant amount of magnetic diffuse scattering which can be fit to the dipolar spin-ice model. However, these short-ranged ordered spins have a quasielastic response that is atypical of the canonical spin ices, and suggests that the ground state is dynamic (i.e., composed of locally ordered two-in-two-out spin configurations that can tunnel between energetically equivalent orientations). We report this as an example of a dynamic spin ice down to 200 mK.
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Affiliation(s)
- H D Zhou
- Department of Physics, Florida State University, Tallahassee, Florida 32306-3016, USA
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Zhou HD, Vogt BW, Janik JA, Jo YJ, Balicas L, Qiu Y, Copley JRD, Gardner JS, Wiebe CR. Partial field-induced magnetic order in the spin-liquid kagomé Nd3Ga5SiO14. Phys Rev Lett 2007; 99:236401. [PMID: 18233386 DOI: 10.1103/physrevlett.99.236401] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2007] [Indexed: 05/25/2023]
Abstract
The distorted kagomé system Nd3Ga5SiO14 has been investigated with neutron scattering down to 0.046 K with no evidence of magnetic long range order of the Nd3+ moments in a zero field. Substantial diffuse scattering is observed which is in agreement with nearest-neighbor correlations between the fluctuating spins. Upon the application of a field in the c direction, the diffuse scattering is reduced in intensity while the magnetic Bragg peaks grow in intensity to saturate by 1 T to 1/2 of the expected magnetization. These measurements suggest that a unique spin-liquid state develops in Nd3Ga5SiO14 with a frustration index of f approximately |theta|/T_{C}> or =1300.
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Affiliation(s)
- H D Zhou
- Department of Physics, Florida State University, Tallahassee, Florida 32306-3016, USA
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