1
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Structural order-disorder in CaFe6Ge6 and Ca1-xCo6Ge6. J SOLID STATE CHEM 2022. [DOI: 10.1016/j.jssc.2022.123742] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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2
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Kim J, Kim K, Choi E, Joon Ko Y, Woo Lee D, Ho Lim S, Hoon Jung J, Lee S. Magnetic phase diagram of a 2-dimensional triangular lattice antiferromagnet Na 2BaMn(PO 4) 2. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2022; 34:475803. [PMID: 36174545 DOI: 10.1088/1361-648x/ac965f] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2022] [Accepted: 09/29/2022] [Indexed: 06/16/2023]
Abstract
We report the magnetic phase transitions of a spin-5/2, 2-dimensional triangular lattice antiferromagnet (AFM) Na2BaMn(PO4)2. From specific heat measurements, we observe two magnetic transitions at temperatures 1.15 and 1.30 K at zero magnetic field. Detailed AC magnetic susceptibility measurements reveal multiple phases including the↑↑↓(up-up-down)-phase between 1.9 and 2.9 T at 47 mK when magnetic field is applied along thecaxis, implying that Na2BaMn(PO4)2is a classical 2dTL Heisenberg AFM with easy-axis anisotropy. However, it deviates from an ideal model as evidenced by a hump region with hysteresis between the↑↑↓andV-phases and weak phase transitions. Our work provides another experimental example to study frustrated magnetism in 2dTL AFM which also serves as a reference to understand the possible quantum spin liquid behavior and anomalous phase diagrams observed in sibling systems Na2BaM(PO4)2(M= Co, Ni).
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Affiliation(s)
- Jaewook Kim
- Korea Atomic Energy Research Institute, Daejeon 34057, Republic of Korea
| | - Kyoo Kim
- Korea Atomic Energy Research Institute, Daejeon 34057, Republic of Korea
| | - Eunsang Choi
- National High Magnetic Field Laboratory, Florida State University, Tallahassee, FL 32310-3706, United States of America
| | - Young Joon Ko
- Department of Physics, Inha University, Incheon 22212, Republic of Korea
| | - Dong Woo Lee
- Korea Atomic Energy Research Institute, Daejeon 34057, Republic of Korea
| | - Sang Ho Lim
- Korea Atomic Energy Research Institute, Daejeon 34057, Republic of Korea
| | - Jong Hoon Jung
- Department of Physics, Inha University, Incheon 22212, Republic of Korea
| | - Seungsu Lee
- Korea Atomic Energy Research Institute, Daejeon 34057, Republic of Korea
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3
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Yahne DR, Pereira D, Jaubert LDC, Sanjeewa LD, Powell M, Kolis JW, Xu G, Enjalran M, Gingras MJP, Ross KA. Understanding Reentrance in Frustrated Magnets: The Case of the Er_{2}Sn_{2}O_{7} Pyrochlore. PHYSICAL REVIEW LETTERS 2021; 127:277206. [PMID: 35061439 DOI: 10.1103/physrevlett.127.277206] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2021] [Accepted: 11/11/2021] [Indexed: 06/14/2023]
Abstract
Reentrance, the return of a system from an ordered phase to a previously encountered less-ordered one as a controlled parameter is continuously varied, is a recurring theme found in disparate physical systems, yet its microscopic cause is often not investigated thoroughly. Here, through detailed characterization and theoretical modeling, we uncover the microscopic mechanism behind reentrance in the strongly frustrated pyrochlore antiferromagnet Er_{2}Sn_{2}O_{7}. We use single crystal heat capacity measurements to expose that Er_{2}Sn_{2}O_{7} exhibits multiple instances of reentrance in its magnetic field B vs temperature T phase diagram for magnetic fields along three cubic high symmetry directions. Through classical Monte Carlo simulations, mean field theory, and classical linear spin-wave expansions, we argue that the origins of the multiple occurrences of reentrance observed in Er_{2}Sn_{2}O_{7} are linked to soft modes. These soft modes arise from phase competition and enhance thermal fluctuations that entropically stabilize a specific ordered phase, resulting in an increased transition temperature for certain field values and thus the reentrant behavior. Our work represents a detailed examination into the mechanisms responsible for reentrance in a frustrated magnet and may serve as a template for the interpretation of reentrant phenomena in other physical systems.
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Affiliation(s)
- D R Yahne
- Department of Physics, Colorado State University, 200 W. Lake Street, Fort Collins, Colorado 80523-1875, USA
| | - D Pereira
- Department of Physics and Astronomy, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada
| | - L D C Jaubert
- CNRS, Université de Bordeaux, LOMA, UMR 5798, 33400 Talence, France
| | - L D Sanjeewa
- Missouri Research Reactor, University of Missouri, Columbia, Missouri 65211, USA
- Department of Chemistry, University of Missouri, Columbia, Missouri 65211, USA
| | - M Powell
- Department of Chemistry, Clemson University, Clemson, South Carolina 29634-0973, USA
| | - J W Kolis
- Department of Chemistry, Clemson University, Clemson, South Carolina 29634-0973, USA
| | - Guangyong Xu
- NIST Center for Neutron Research, National Institutue of Standards and Technology, Gaithersburg, Maryland 20899, USA
| | - M Enjalran
- Department of Physics, Southern Connecticut State University, 501 Crescent Street, New Haven, Connecticut 06515-1355, USA
| | - M J P Gingras
- Department of Physics and Astronomy, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada
- CIFAR, MaRS Centre, West Tower 661 University Avenue, Suite 505, Toronto, Ontario M5G 1M1, Canada
| | - K A Ross
- Department of Physics, Colorado State University, 200 W. Lake Street, Fort Collins, Colorado 80523-1875, USA
- CIFAR, MaRS Centre, West Tower 661 University Avenue, Suite 505, Toronto, Ontario M5G 1M1, Canada
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Kermarrec E, Kumar R, Bernard G, Hénaff R, Mendels P, Bert F, Paulose PL, Hazra BK, Koteswararao B. Classical Spin Liquid State in the S=5/2 Heisenberg Kagome Antiferromagnet Li_{9}Fe_{3}(P_{2}O_{7})_{3}(PO_{4})_{2}. PHYSICAL REVIEW LETTERS 2021; 127:157202. [PMID: 34678038 DOI: 10.1103/physrevlett.127.157202] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/04/2021] [Revised: 07/14/2021] [Accepted: 09/16/2021] [Indexed: 06/13/2023]
Abstract
We investigate the low temperature magnetic properties of a S=5/2 Heisenberg kagome antiferromagnet, the layered monodiphosphate Li_{9}Fe_{3}(P_{2}O_{7})_{3}(PO_{4})_{2}, using magnetization measurements and ^{31}P nuclear magnetic resonance. An antiferromagnetic-type order sets in at T_{N}=1.3 K and a characteristic magnetization plateau is observed at 1/3 of the saturation magnetization below T^{*}∼5 K. A moderate ^{31}P NMR line broadening reveals the development of anisotropic short-range correlations concomitantly with a gapless spin-lattice relaxation time T_{1}∼k_{B}T/ℏS, which may point to the presence of a semiclassical nematic spin-liquid state predicted for the Heisenberg kagome antiferromagnetic model or to the persistence of the zero-energy modes of the kagome lattice under large magnetic fields.
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Affiliation(s)
- E Kermarrec
- Université Paris-Saclay, CNRS, Laboratoire de Physique des Solides, 91405 Orsay, France
| | - R Kumar
- Université Paris-Saclay, CNRS, Laboratoire de Physique des Solides, 91405 Orsay, France
| | - G Bernard
- Université Paris-Saclay, CNRS, Laboratoire de Physique des Solides, 91405 Orsay, France
| | - R Hénaff
- Université Paris-Saclay, CNRS, Laboratoire de Physique des Solides, 91405 Orsay, France
| | - P Mendels
- Université Paris-Saclay, CNRS, Laboratoire de Physique des Solides, 91405 Orsay, France
| | - F Bert
- Université Paris-Saclay, CNRS, Laboratoire de Physique des Solides, 91405 Orsay, France
| | - P L Paulose
- Department of Condensed Matter Physics and Materials Science, TIFR, Mumbai 400 005, India
| | - B K Hazra
- School of Physics, University of Hyderabad, Hyderabad 500046, India
| | - B Koteswararao
- Department of Physics, Indian Institute of Technology Tirupati, Tirupati 517506, India
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5
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Gómez Albarracín FA, Rosales HD. Multiple pseudo-plateaux states and antiferromagnetic pair selection in the XY model in the highly frustrated honeycomb lattice. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2021; 33:185801. [PMID: 33761484 DOI: 10.1088/1361-648x/abf19c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/08/2021] [Accepted: 03/23/2021] [Indexed: 06/12/2023]
Abstract
We present a study of the low temperature magnetic phases of the classicalXYmodel with third nearest neighbor interactions on the honeycomb lattice at the maximally frustrated point under an external magnetic field by extensive Monte Carlo simulations. We focus on the characterization of the emergent low temperature phases, which are a direct consequence of the unusually high numbers of spins per plaquette in the model. Specifically, we show that, since thermal fluctuations partially lift the ground-state degeneracy and select the most collinear states, the selected states are those with the highest number of 'antiferromagnetic pairs' (AFp) compatible with the external magnetic field. These AFp are formed in such a way that they maximize the degeneracy of the selected submanifold of ground states. Moreover, two collinear pseudoplateaux emerge atM= 1/3 andM= 2/3. To characterize the magnetization process, we employ Monte Carlo simulations and calculate relevant order parameters to construct the complete temperature vs magnetic field phase diagram.
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Affiliation(s)
- F A Gómez Albarracín
- Instituto de Física de Líquidos y Sistemas Biológicos, CONICET, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, 1900 La Plata, Argentina
- Departamento de Física, FCE, UNLP, La Plata, Argentina
- Departamento de Ciencias Básicas, Facultad de Ingeniería, UNLP, La Plata, Argentina
| | - H D Rosales
- Instituto de Física de Líquidos y Sistemas Biológicos, CONICET, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, 1900 La Plata, Argentina
- Departamento de Física, FCE, UNLP, La Plata, Argentina
- Departamento de Ciencias Básicas, Facultad de Ingeniería, UNLP, La Plata, Argentina
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Yamamoto D, Suzuki C, Marmorini G, Okazaki S, Furukawa N. Quantum and Thermal Phase Transitions of the Triangular SU(3) Heisenberg Model under Magnetic Fields. PHYSICAL REVIEW LETTERS 2020; 125:057204. [PMID: 32794836 DOI: 10.1103/physrevlett.125.057204] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Accepted: 07/15/2020] [Indexed: 06/11/2023]
Abstract
We study the quantum and thermal phase transition phenomena of the SU(3) Heisenberg model on triangular lattice in the presence of magnetic fields. Performing a scaling analysis on large-size cluster mean-field calculations endowed with a density-matrix renormalization-group solver, we reveal the quantum phases selected by quantum fluctuations from the massively degenerate classical ground-state manifold. The magnetization process up to saturation reflects three different magnetic phases. The low- and high-field phases have strong nematic nature, and especially the latter is found only via a nontrivial reconstruction of symmetry generators from the standard spin and quadrupolar description. We also perform a semiclassical Monte Carlo simulation to show that thermal fluctuations prefer the same three phases as well. Moreover, we find that exotic topological phase transitions driven by the binding-unbinding of fractional (half-)vortices take place, due to the nematicity of the low- and high-field phases. Possible experimental realization with alkaline-earth-like cold atoms is also discussed.
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Affiliation(s)
- Daisuke Yamamoto
- Department of Physics and Mathematics, Aoyama Gakuin University, Sagamihara, Kanagawa 252-5258, Japan
| | - Chihiro Suzuki
- Department of Physics and Mathematics, Aoyama Gakuin University, Sagamihara, Kanagawa 252-5258, Japan
| | - Giacomo Marmorini
- Department of Physics and Mathematics, Aoyama Gakuin University, Sagamihara, Kanagawa 252-5258, Japan
| | - Sho Okazaki
- Department of Physics and Mathematics, Aoyama Gakuin University, Sagamihara, Kanagawa 252-5258, Japan
| | - Nobuo Furukawa
- Department of Physics and Mathematics, Aoyama Gakuin University, Sagamihara, Kanagawa 252-5258, Japan
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Li M, Plumer ML, Quirion G. Effects of interlayer and bi-quadratic exchange coupling on layered triangular lattice antiferromagnets. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2020; 32:135803. [PMID: 31801115 DOI: 10.1088/1361-648x/ab5ea6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
The magnetic field evolution of ground spin states of the stacked planar triangular antiferromagnet with antiferromagnetic interlayer interaction J c is explored using a minimal 3D classical Heisenberg model. A bi-quadratic coupling is also used to mimic the effect of spin fluctuations (Zhitomirsky 2015 J. Phys.: Conf. Ser. 592 012110) which are known to stabilize the magnetization plateau. A single ion anisotropy is included and states with a magnetic field applied in the ab plane and along the c axis are determined. For [Formula: see text]-plane, an additional new state, in contrast to 2D model (Zhitomirsky 2015 J. Phys.: Conf. Ser. 592 012110), is obtained with weak interlayer interaction, while the magnetization plateau vanishes at large J c and other new states with z components of spins emerge. For [Formula: see text]-axis, an extra state, compared with 2D model, is obtained with a weak interlayer interaction. When J c is large enough, only the state corresponding to the Umbrella phase in 2D model exits.
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Affiliation(s)
- M Li
- Department of Physics and Physical Oceanography, Memorial University, St. John's, Newfoundland A1B 3X7, Canada
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Gómez Albarracín FA, Rosales HD, Serra P. Phase transitions, order by disorder, and finite entropy in the Ising antiferromagnetic bilayer honeycomb lattice. Phys Rev E 2018; 98:012139. [PMID: 30110814 DOI: 10.1103/physreve.98.012139] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2018] [Indexed: 11/07/2022]
Abstract
We present an analytical and numerical study of the Ising model on a bilayer honeycomb lattice including interlayer frustration and coupling with an external magnetic field. First, we discuss the exact T=0 phase diagram, where we find finite entropy phases for different magnetizations. Then, we study the magnetic properties of the system at finite temperature using complementary analytical techniques (Bethe lattice) and two types of Monte Carlo algorithms (Metropolis and Wang-Landau). We characterize the phase transitions and discuss the phase diagrams. The system presents a rich phenomenology: There are first- and second-order transitions, low-temperature phases with extensive degeneracy, and order-by-disorder state selection.
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Affiliation(s)
- F A Gómez Albarracín
- Instituto de Física de La Plata -CONICET. Facultad de Ciencias Exactas, Universidad Nacional de La Plata, C.C. 67, 1900 La Plata, Argentina.,Departamento de Física, FCE, UNLP, La Plata, Argentina
| | - H D Rosales
- Instituto de Física de La Plata -CONICET. Facultad de Ciencias Exactas, Universidad Nacional de La Plata, C.C. 67, 1900 La Plata, Argentina.,Departamento de Física, FCE, UNLP, La Plata, Argentina
| | - Pablo Serra
- Facultad de Matemática, Astronomía, Física y Computación, Universidad Nacional de Córdoba and IFEG-CONICET, Ciudad Universitaria, X5016LAE Córdoba, Argentina
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9
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Liu M, Zhang H, Huang X, Ma C, Dong S, Liu JM. Two-Step Antiferromagnetic Transitions and Ferroelectricity in Spin-1 Triangular-Lattice Antiferromagnetic Sr3NiTa2O9. Inorg Chem 2016; 55:2709-16. [PMID: 26934503 DOI: 10.1021/acs.inorgchem.5b02270] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
We report the low-temperature characterizations on structural, specific heat, magnetic, and ferroelectric behaviors of transition metal oxide compound Sr3NiTa2O9. It is suggested that Sr3NiTa2O9 is a spin-1 triangular lattice Heisenberg quantum antiferromagnet which may have weak easy-axis anisotropy. At zero magnetic field, a two-step transition sequence at T(N1) = 3.35 K and T(N2) = 2.74 K, respectively, is observed, corresponding to the up-up-down (uud) spin ordering and 120° spin ordering, respectively. The two transition points shift gradually with increasing magnetic field toward the low temperature, accompanying an evolution from the 120° spin structure (phase) to the normal oblique phases. Ferroelectricity in the 120° phase is clearly identified. The first-principles calculations confirm the 120° phase as the ground state whose ferroelectricity originates mainly from the electronic polarization.
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Affiliation(s)
- Meifeng Liu
- Laboratory of Solid State Microstructures and Innovative Center of Advanced Microstructures, Nanjing University , Nanjing 210093, China
| | - Huimin Zhang
- Department of Physics, Southeast University , Nanjing 211189, China
| | - Xin Huang
- Department of Physics, Southeast University , Nanjing 211189, China
| | - Chunyang Ma
- Laboratory of Solid State Microstructures and Innovative Center of Advanced Microstructures, Nanjing University , Nanjing 210093, China
| | - Shuai Dong
- Department of Physics, Southeast University , Nanjing 211189, China
| | - Jun-Ming Liu
- Laboratory of Solid State Microstructures and Innovative Center of Advanced Microstructures, Nanjing University , Nanjing 210093, China.,Institute for Advanced Materials and Laboratory of Quantum Engineering and Materials, South China Normal University , Guangzhou 510006, China
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Starykh OA. Unusual ordered phases of highly frustrated magnets: a review. REPORTS ON PROGRESS IN PHYSICS. PHYSICAL SOCIETY (GREAT BRITAIN) 2015; 78:052502. [PMID: 25892088 DOI: 10.1088/0034-4885/78/5/052502] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
We review ground states and excitations of a quantum antiferromagnet on triangular and other frustrated lattices. We pay special attention to the combined effects of magnetic field h, spatial anisotropy R and spin magnitude S. The focus of the review is on the novel collinear spin density wave and spin nematic states, which are characterized by fully gapped transverse spin excitations with S(z) = ± 1. We discuss extensively the R - h phase diagram of the antiferromagnet, both in the large-S semiclassical limit and the quantum S = 1/2 limit. When possible, we point out connections with experimental findings.
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Affiliation(s)
- Oleg A Starykh
- Department of Physics and Astronomy, University of Utah, Salt Lake City, UT 84112-0830, USA
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11
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Freitas AS, de Albuquerque DF. Existence of a tricritical point in the antiferromagnet KFe3(OH)6(SO4)2 on a kagome lattice. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2015; 91:012117. [PMID: 25679580 DOI: 10.1103/physreve.91.012117] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/19/2014] [Indexed: 06/04/2023]
Abstract
We study the phase diagram in the H-T plane of the potassium jarosite compound KFe(3)(OH)(6)(SO(4))(2) for the antiferromagnetic XY model with Dzyaloshinskii-Moriya (DM) interaction using the mean-field theory for different value of DM. In our approach, we obtain the tricritical point in the H-T plane and the adjustment has a strong correlation with experimental data.
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Affiliation(s)
- A S Freitas
- Departamento de Física, Universidade Federal de Sergipe, 49100-000 São Cristovão, SE, Brazil and Coordenadoria de Licenciatura em Física, Instituto Federal de Sergipe, 49400-000 Lagarto, SE, Brazil
| | - Douglas F de Albuquerque
- Departamento de Física, Universidade Federal de Sergipe, 49100-000 São Cristovão, SE, Brazil and Departamento de Matemática, Universidade Federal de Sergipe, 49100-000 São Cristovão, SE, Brazil
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12
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Maryasin VS, Zhitomirsky ME. Triangular antiferromagnet with nonmagnetic impurities. PHYSICAL REVIEW LETTERS 2013; 111:247201. [PMID: 24483694 DOI: 10.1103/physrevlett.111.247201] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/26/2013] [Revised: 11/19/2013] [Indexed: 06/03/2023]
Abstract
The effect of nonmagnetic impurities on the phase diagram of the classical Heisenberg antiferromagnet on a triangular lattice is investigated. We present analytical arguments confirmed by numerical calculations that at zero temperature vacancies stabilize a conical state providing an example of "order by quenched disorder" effect. Competition between thermal fluctuations and the site disorder leads to a complicated H-T phase diagram, which is deduced from the classical Monte Carlo simulations for a representative vacancy concentration. For the XY triangular-lattice antiferromagnet with an in-plane external field, nonmagnetic impurities stabilize the fanlike spin structure. We also briefly discuss the effect of quantum fluctuations.
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Affiliation(s)
- V S Maryasin
- Service de Physique Statistique, Magnétisme et Supraconductivité, UMR-E9001 CEA-INAC/UJF, 17 rue des Martyrs, 38054 Grenoble, France
| | - M E Zhitomirsky
- Service de Physique Statistique, Magnétisme et Supraconductivité, UMR-E9001 CEA-INAC/UJF, 17 rue des Martyrs, 38054 Grenoble, France
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Kulagin SA, Prokof'ev N, Starykh OA, Svistunov B, Varney CN. Bold diagrammatic Monte Carlo method applied to fermionized frustrated spins. PHYSICAL REVIEW LETTERS 2013; 110:070601. [PMID: 25166359 DOI: 10.1103/physrevlett.110.070601] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2012] [Indexed: 06/03/2023]
Abstract
We demonstrate, by considering the triangular lattice spin-1/2 Heisenberg model, that Monte Carlo sampling of skeleton Feynman diagrams within the fermionization framework offers a universal first-principles tool for strongly correlated lattice quantum systems. We observe the fermionic sign blessing--cancellation of higher order diagrams leading to a finite convergence radius of the series. We calculate the magnetic susceptibility of the triangular-lattice quantum antiferromagnet in the correlated paramagnet regime and reveal a surprisingly accurate microscopic correspondence with its classical counterpart at all accessible temperatures. The extrapolation of the observed relation to zero temperature suggests the absence of the magnetic order in the ground state. We critically examine the implications of this unusual scenario.
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Affiliation(s)
- S A Kulagin
- Department of Physics, University of Massachusetts, Amherst, Massachusetts 01003, USA and Institute for Nuclear Research of Russian Academy of Sciences, 117312 Moscow, Russia
| | - N Prokof'ev
- Department of Physics, University of Massachusetts, Amherst, Massachusetts 01003, USA and Russian Research Center "Kurchatov Institute," 123182 Moscow, Russia
| | - O A Starykh
- Department of Physics and Astronomy, University of Utah, Salt Lake City, Utah 84112, USA
| | - B Svistunov
- Department of Physics, University of Massachusetts, Amherst, Massachusetts 01003, USA and Russian Research Center "Kurchatov Institute," 123182 Moscow, Russia
| | - C N Varney
- Department of Physics, University of Massachusetts, Amherst, Massachusetts 01003, USA
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14
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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. PHYSICAL REVIEW LETTERS 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] [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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15
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Okubo T, Chung S, Kawamura H. Multiple-q states and the Skyrmion lattice of the triangular-lattice Heisenberg antiferromagnet under magnetic fields. PHYSICAL REVIEW LETTERS 2012; 108:017206. [PMID: 22304286 DOI: 10.1103/physrevlett.108.017206] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2011] [Indexed: 05/31/2023]
Abstract
Ordering of the frustrated classical Heisenberg model on the triangular lattice with an incommensurate spiral structure is studied under magnetic fields by means of a mean-field analysis and a Monte Carlo simulation. Several types of multiple-q states including the Skyrmion-lattice state is observed in addition to the standard single-q state. In contrast to the Dzyaloshinskii-Moriya interaction driven system, the present model allows both Skyrmions and anti-Skyrmions, together with a new thermodynamic phase where Skyrmion and anti-Skyrmion lattices form a domain state.
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Affiliation(s)
- Tsuyoshi Okubo
- Department of Earth and Space Science, Faculty of Science, Osaka University, Toyonaka, Osaka 560-0043, Japan.
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