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Kim S, Zhu J, Piva MM, Schmidt M, Fartab D, Mackenzie AP, Baenitz M, Nicklas M, Rosner H, Cook AM, González‐Hernández R, Šmejkal L, Zhang H. Observation of the Anomalous Hall Effect in a Layered Polar Semiconductor. Adv Sci (Weinh) 2024; 11:e2307306. [PMID: 38063838 PMCID: PMC10853720 DOI: 10.1002/advs.202307306] [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] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/04/2023] [Indexed: 02/10/2024]
Abstract
Progress in magnetoelectric materials is hindered by apparently contradictory requirements for time-reversal symmetry broken and polar ferroelectric electronic structure in common ferromagnets and antiferromagnets. Alternative routes can be provided by recent discoveries of a time-reversal symmetry breaking anomalous Hall effect (AHE) in noncollinear magnets and altermagnets, but hitherto reported bulk materials are not polar. Here, the authors report the observation of a spontaneous AHE in doped AgCrSe2 , a layered polar semiconductor with an antiferromagnetic coupling between Cr spins in adjacent layers. The anomalous Hall resistivity 3μ Ω c m $\mu \Omega \, \textnormal {cm}$ is comparable to the largest observed in compensated magnetic systems to date, and is rapidly switched off when the angle of an applied magnetic field is rotated to ≈80° from the crystalline c-axis. The ionic gating experiments show that the anomalous Hall conductivity magnitude can be enhanced by modulating the p-type carrier density. They also present theoretical results that suggest the AHE is driven by Berry curvature due to noncollinear antiferromagnetic correlations among Cr spins, which are consistent with the previously suggested magnetic ordering in AgCrSe2 . The results open the possibility to study the interplay of magnetic and ferroelectric-like responses in this fascinating class of materials.
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Affiliation(s)
- Seo‐Jin Kim
- Max Planck Institute for Chemical Physics of Solids01187DresdenGermany
| | - Jihang Zhu
- Max Planck Institute for the Physics of Complex Systems01187DresdenGermany
| | - Mario M. Piva
- Max Planck Institute for Chemical Physics of Solids01187DresdenGermany
| | - Marcus Schmidt
- Max Planck Institute for Chemical Physics of Solids01187DresdenGermany
| | - Dorsa Fartab
- Max Planck Institute for Chemical Physics of Solids01187DresdenGermany
| | - Andrew P. Mackenzie
- Max Planck Institute for Chemical Physics of Solids01187DresdenGermany
- Scottish Universities Physics AllianceSchool of Physics and AstronomyUniversity of St AndrewsSt AndrewsKY16 9SSUnited Kingdom
| | - Michael Baenitz
- Max Planck Institute for Chemical Physics of Solids01187DresdenGermany
| | - Michael Nicklas
- Max Planck Institute for Chemical Physics of Solids01187DresdenGermany
| | - Helge Rosner
- Max Planck Institute for Chemical Physics of Solids01187DresdenGermany
| | - Ashley M. Cook
- Max Planck Institute for Chemical Physics of Solids01187DresdenGermany
- Max Planck Institute for the Physics of Complex Systems01187DresdenGermany
| | - Rafael González‐Hernández
- Institut für PhysikJohannes Gutenberg Universität Mainz55128MainzGermany
- Grupo de Investigación en Física AplicadaDepartamento de FísicaUniversidad del NorteBarranquilla080020Colombia
| | - Libor Šmejkal
- Institut für PhysikJohannes Gutenberg Universität Mainz55128MainzGermany
- Institute of PhysicsCzech Academy of SciencesCukrovarnická 10Praha 6162 00Czech Republic
| | - Haijing Zhang
- Max Planck Institute for Chemical Physics of Solids01187DresdenGermany
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Zhakina E, Daou R, Maignan A, McGuinness PH, König M, Rosner H, Kim SJ, Khim S, Grasset R, Konczykowski M, Tulipman E, Mendez-Valderrama JF, Chowdhury D, Berg E, Mackenzie AP. Investigation of Planckian behavior in a high-conductivity oxide: PdCrO 2. Proc Natl Acad Sci U S A 2023; 120:e2307334120. [PMID: 37639594 PMCID: PMC10483643 DOI: 10.1073/pnas.2307334120] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2023] [Accepted: 06/23/2023] [Indexed: 08/31/2023] Open
Abstract
The layered delafossite metal PdCrO[Formula: see text] is a natural heterostructure of highly conductive Pd layers Kondo coupled to localized spins in the adjacent Mott insulating CrO[Formula: see text] layers. At high temperatures, T, it has a T-linear resistivity which is not seen in the isostructural but nonmagnetic PdCoO[Formula: see text]. The strength of the Kondo coupling is known, as-grown crystals are extremely high purity and the Fermi surface is both very simple and experimentally known. It is therefore an ideal material platform in which to investigate "Planckian metal" physics. We do this by means of controlled introduction of point disorder, measurement of the thermal conductivity and Lorenz ratio, and studying the sources of its high-temperature entropy. The T-linear resistivity is seen to be due mainly to elastic scattering and to arise from a sum of several scattering mechanisms. Remarkably, this sum leads to a scattering rate within 10[Formula: see text] of the Planckian value of k[Formula: see text]T/[Formula: see text].
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Affiliation(s)
- Elina Zhakina
- Max Planck Institute for Chemical Physics of Solids, Dresden01187, Germany
| | - Ramzy Daou
- Laboratoire de Cristallographie et Sciences des Matériaux, Normandie Université, UMR6508 CNRS, ENSICAEN, UNICAEN, Caen14000, France
| | - Antoine Maignan
- Laboratoire de Cristallographie et Sciences des Matériaux, Normandie Université, UMR6508 CNRS, ENSICAEN, UNICAEN, Caen14000, France
| | | | - Markus König
- Max Planck Institute for Chemical Physics of Solids, Dresden01187, Germany
| | - Helge Rosner
- Max Planck Institute for Chemical Physics of Solids, Dresden01187, Germany
| | - Seo-Jin Kim
- Max Planck Institute for Chemical Physics of Solids, Dresden01187, Germany
| | - Seunghyun Khim
- Max Planck Institute for Chemical Physics of Solids, Dresden01187, Germany
| | - Romain Grasset
- Laboratoire des Solides Irradiés, CEA/DRF/IRAMIS, Ecole Polytechnique, CNRS, Institut Polytechnique de Paris, PalaiseauF-91128, France
| | - Marcin Konczykowski
- Laboratoire des Solides Irradiés, CEA/DRF/IRAMIS, Ecole Polytechnique, CNRS, Institut Polytechnique de Paris, PalaiseauF-91128, France
| | - Evyatar Tulipman
- Department of Condensed Matter Physics, Weizmann Institute of Science, Rehovot76100, Israel
| | | | | | - Erez Berg
- Department of Condensed Matter Physics, Weizmann Institute of Science, Rehovot76100, Israel
| | - Andrew P. Mackenzie
- Max Planck Institute for Chemical Physics of Solids, Dresden01187, Germany
- Scottish Universities Physics Alliance, School of Physics and Astronomy, University of St. Andrews, St. AndrewsKY16 9SS, United Kingdom
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Jerzembeck F, Røising HS, Steppke A, Rosner H, Sokolov DA, Kikugawa N, Scaffidi T, Simon SH, Mackenzie AP, Hicks CW. The superconductivity of Sr 2RuO 4 under c-axis uniaxial stress. Nat Commun 2022; 13:4596. [PMID: 35933412 PMCID: PMC9357014 DOI: 10.1038/s41467-022-32177-4] [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] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2022] [Accepted: 07/19/2022] [Indexed: 11/15/2022] Open
Abstract
Applying in-plane uniaxial pressure to strongly correlated low-dimensional systems has been shown to tune the electronic structure dramatically. For example, the unconventional superconductor Sr2RuO4 can be tuned through a single Van Hove point, resulting in strong enhancement of both Tc and Hc2. Out-of-plane (c axis) uniaxial pressure is expected to tune the quasi-two-dimensional structure even more strongly, by pushing it towards two Van Hove points simultaneously. Here, we achieve a record uniaxial stress of 3.2 GPa along the c axis of Sr2RuO4. Hc2 increases, as expected for increasing density of states, but unexpectedly Tc falls. As a first attempt to explain this result, we present three-dimensional calculations in the weak interaction limit. We find that within the weak-coupling framework there is no single order parameter that can account for the contrasting effects of in-plane versus c-axis uniaxial stress, which makes this new result a strong constraint on theories of the superconductivity of Sr2RuO4. In the superconductor Sr2RuO4, in-plane strain is known to enhance both the superconducting transition temperature Tc and upper critical field Hc2, but the effect of out-of-plane strain has not been studied. Here, the authors find that Hc2 is enhanced under out-of-plane strain, but Tc unexpectedly decreases.
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Affiliation(s)
- Fabian Jerzembeck
- Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Str 40, 01187, Dresden, Germany.
| | - Henrik S Røising
- Nordita, KTH Royal Institute of Technology and Stockholm University, Hannes Alfvéns väg 12, SE-106 91, Stockholm, Sweden
| | - Alexander Steppke
- Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Str 40, 01187, Dresden, Germany
| | - Helge Rosner
- Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Str 40, 01187, Dresden, Germany
| | - Dmitry A Sokolov
- Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Str 40, 01187, Dresden, Germany
| | - Naoki Kikugawa
- National Institute for Materials Science, Tsukuba, 305-0003, Japan
| | - Thomas Scaffidi
- Department of Physics, University of Toronto, Toronto, ON, M5S 1A7, Canada.,Department of Physics and Astronomy, University of California, Irvine, CA, 92697, USA
| | - Steven H Simon
- Rudolf Peierls Center for Theoretical Physics, Oxford, OX1 3PU, UK
| | - Andrew P Mackenzie
- Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Str 40, 01187, Dresden, Germany. .,Scottish Universities Physics Alliance, School of Physics and Astronomy, University of St. Andrews, St. Andrews, KY16 9SS, UK.
| | - Clifford W Hicks
- Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Str 40, 01187, Dresden, Germany. .,School of Physics and Astronomy, University of Birmingham, Birmingham, B15 2TT, UK.
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Kibune M, Kitagawa S, Kinjo K, Ogata S, Manago M, Taniguchi T, Ishida K, Brando M, Hassinger E, Rosner H, Geibel C, Khim S. Observation of Antiferromagnetic Order as Odd-Parity Multipoles inside the Superconducting Phase in CeRh_{2}As_{2}. Phys Rev Lett 2022; 128:057002. [PMID: 35179930 DOI: 10.1103/physrevlett.128.057002] [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] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2021] [Accepted: 11/03/2021] [Indexed: 06/14/2023]
Abstract
Spatial inversion symmetry in crystal structures is closely related to the superconducting (SC) and magnetic properties of materials. Recently, several theoretical proposals that predict various interesting phenomena caused by the breaking of the local inversion symmetry have been presented. However, experimental validation has not yet progressed owing to the lack of model materials. Here we present evidence for antiferromagnetic (AFM) order in CeRh_{2}As_{2} (SC transition temperature T_{SC}∼0.37 K), wherein the Ce site breaks the local inversion symmetry. The evidence is based on the observation of different extents of broadening of the nuclear quadrupole resonance spectrum at two crystallographically inequivalent As sites. This AFM ordering breaks the inversion symmetry of this system, resulting in the activation of an odd-parity magnetic multipole. Moreover, the onset of antiferromagnetism T_{N} within an SC phase, with T_{N}<T_{SC}, is quite unusual in systems wherein superconductivity coexists or competes with magnetism. Our observations show that CeRh_{2}As_{2} is a promising system to study how the absence of local inversion symmetry induces or influences unconventional magnetic and SC states, as well as their interaction.
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Affiliation(s)
- Mayu Kibune
- Department of Physics, Kyoto University, Kyoto 606-8502, Japan
| | | | - Katsuki Kinjo
- Department of Physics, Kyoto University, Kyoto 606-8502, Japan
| | - Shiki Ogata
- Department of Physics, Kyoto University, Kyoto 606-8502, Japan
| | - Masahiro Manago
- Department of Physics, Kyoto University, Kyoto 606-8502, Japan
| | | | - Kenji Ishida
- Department of Physics, Kyoto University, Kyoto 606-8502, Japan
| | - Manuel Brando
- Max Planck Institute for Chemical Physics of Solids, D-01187 Dresden, Germany
| | - Elena Hassinger
- Max Planck Institute for Chemical Physics of Solids, D-01187 Dresden, Germany
| | - Helge Rosner
- Max Planck Institute for Chemical Physics of Solids, D-01187 Dresden, Germany
| | - Christoph Geibel
- Max Planck Institute for Chemical Physics of Solids, D-01187 Dresden, Germany
| | - Seunghyun Khim
- Max Planck Institute for Chemical Physics of Solids, D-01187 Dresden, Germany
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Mydeen K, Jesche A, Meier-Kirchner K, Schwarz U, Geibel C, Rosner H, Nicklas M. Electron Doping of the Iron-Arsenide Superconductor CeFeAsO Controlled by Hydrostatic Pressure. Phys Rev Lett 2020; 125:207001. [PMID: 33258641 DOI: 10.1103/physrevlett.125.207001] [Citation(s) in RCA: 1] [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: 07/15/2020] [Revised: 09/25/2020] [Accepted: 10/14/2020] [Indexed: 06/12/2023]
Abstract
In the iron-pnictide material CeFeAsO not only the Fe moments, but also the local 4f moments of the Ce order antiferromagnetically at low temperatures. We elucidate on the peculiar role of the Ce on the emergence of superconductivity. While application of pressure suppresses the iron SDW ordering temperature monotonously up to 4 GPa, the Ce-4f magnetism is stabilized until both types of magnetic orders disappear abruptly and a narrow SC dome develops. With further increasing pressure characteristics of a Kondo-lattice system become more and more apparent in the electrical resistivity. This suggests a connection of the emergence of superconductivity with the extinction of the magnetic order and the onset of Kondo screening of the Ce-4f moments.
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Affiliation(s)
- K Mydeen
- Max-Planck Institute for Chemical Physics of Solids, Nöthnitzer Straße 40, 01187 Dresden
| | - A Jesche
- Max-Planck Institute for Chemical Physics of Solids, Nöthnitzer Straße 40, 01187 Dresden
- Experimental Physics VI, Center for Electronic Correlations and Magnetism, Institute of Physics, University of Augsburg, 86135 Augsburg, Germany
| | - K Meier-Kirchner
- Max-Planck Institute for Chemical Physics of Solids, Nöthnitzer Straße 40, 01187 Dresden
| | - U Schwarz
- Max-Planck Institute for Chemical Physics of Solids, Nöthnitzer Straße 40, 01187 Dresden
| | - C Geibel
- Max-Planck Institute for Chemical Physics of Solids, Nöthnitzer Straße 40, 01187 Dresden
| | - H Rosner
- Max-Planck Institute for Chemical Physics of Solids, Nöthnitzer Straße 40, 01187 Dresden
| | - M Nicklas
- Max-Planck Institute for Chemical Physics of Solids, Nöthnitzer Straße 40, 01187 Dresden
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Sunko V, Mazzola F, Kitamura S, Khim S, Kushwaha P, Clark OJ, Watson MD, Marković I, Biswas D, Pourovskii L, Kim TK, Lee TL, Thakur PK, Rosner H, Georges A, Moessner R, Oka T, Mackenzie AP, King PDC. Probing spin correlations using angle-resolved photoemission in a coupled metallic/Mott insulator system. Sci Adv 2020; 6:eaaz0611. [PMID: 32128385 PMCID: PMC7032925 DOI: 10.1126/sciadv.aaz0611] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/08/2019] [Accepted: 10/29/2019] [Indexed: 06/10/2023]
Abstract
A nearly free electron metal and a Mott insulating state can be thought of as opposite ends of the spectrum of possibilities for the motion of electrons in a solid. Understanding their interaction lies at the heart of the correlated electron problem. In the magnetic oxide metal PdCrO2, nearly free and Mott-localized electrons exist in alternating layers, forming natural heterostructures. Using angle-resolved photoemission spectroscopy, quantitatively supported by a strong coupling analysis, we show that the coupling between these layers leads to an "intertwined" excitation that is a convolution of the charge spectrum of the metallic layer and the spin susceptibility of the Mott layer. Our findings establish PdCrO2 as a model system in which to probe Kondo lattice physics and also open new routes to use the a priori nonmagnetic probe of photoemission to gain insights into the spin susceptibility of correlated electron materials.
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Affiliation(s)
- V. Sunko
- SUPA, School of Physics and Astronomy, University of St Andrews, St Andrews KY16 9SS, UK
- Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Straße 40, 01187 Dresden, Germany
| | - F. Mazzola
- SUPA, School of Physics and Astronomy, University of St Andrews, St Andrews KY16 9SS, UK
| | - S. Kitamura
- Max Planck Institute for the Physics of Complex Systems, Nöthnitzer Straße 38, 01187 Dresden, Germany
| | - S. Khim
- Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Straße 40, 01187 Dresden, Germany
| | - P. Kushwaha
- Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Straße 40, 01187 Dresden, Germany
| | - O. J. Clark
- SUPA, School of Physics and Astronomy, University of St Andrews, St Andrews KY16 9SS, UK
| | - M. D. Watson
- SUPA, School of Physics and Astronomy, University of St Andrews, St Andrews KY16 9SS, UK
| | - I. Marković
- SUPA, School of Physics and Astronomy, University of St Andrews, St Andrews KY16 9SS, UK
- Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Straße 40, 01187 Dresden, Germany
| | - D. Biswas
- SUPA, School of Physics and Astronomy, University of St Andrews, St Andrews KY16 9SS, UK
| | - L. Pourovskii
- CPHT, CNRS, Ecole Polytechnique, Institut Polytechnique de Paris, F-91128 Palaiseau, France
- Institut de Physique, Collège de France, 11 place Marcelin Berthelot, 75005 Paris, France
| | - T. K. Kim
- Diamond Light Source, Harwell Campus, Didcot, OX11 0DE, UK
| | - T.-L. Lee
- Diamond Light Source, Harwell Campus, Didcot, OX11 0DE, UK
| | - P. K. Thakur
- Diamond Light Source, Harwell Campus, Didcot, OX11 0DE, UK
| | - H. Rosner
- Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Straße 40, 01187 Dresden, Germany
| | - A. Georges
- CPHT, CNRS, Ecole Polytechnique, Institut Polytechnique de Paris, F-91128 Palaiseau, France
- Institut de Physique, Collège de France, 11 place Marcelin Berthelot, 75005 Paris, France
- Center for Computational Quantum Physics, Flatiron Institute, New York, NY 10010, USA
- DQMP, Université de Genève, 24 quai Ernest Ansermet, CH-1211 Genève, Switzerland
| | - R. Moessner
- Max Planck Institute for the Physics of Complex Systems, Nöthnitzer Straße 38, 01187 Dresden, Germany
| | - T. Oka
- Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Straße 40, 01187 Dresden, Germany
- Max Planck Institute for the Physics of Complex Systems, Nöthnitzer Straße 38, 01187 Dresden, Germany
| | - A. P. Mackenzie
- SUPA, School of Physics and Astronomy, University of St Andrews, St Andrews KY16 9SS, UK
- Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Straße 40, 01187 Dresden, Germany
| | - P. D. C. King
- SUPA, School of Physics and Astronomy, University of St Andrews, St Andrews KY16 9SS, UK
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Förster T, Kraft I, Sheikin I, Bianchi AD, Wosnitza J, Rosner H. Fermi surface of LaFe 2P 2-a detailed density functional study. J Phys Condens Matter 2020; 32:025503. [PMID: 31536970 DOI: 10.1088/1361-648x/ab45fa] [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: 06/10/2023]
Abstract
Angular-dependent de Haas-van Alphen measurements allow the mapping of Fermi surfaces in great detail with high accuracy. Density functional electronic-structure calculations can be carried out with high precision, but depend crucially on the used structural information and the applied calculational approximations. We report in a detailed study the sensitivity of the calculated electronic band structure of the 122 compound LaFe2P2 on (i) the exact P position in the unit cell, parametrized by a so-called z parameter, and on (ii) the treatment of the La 4f states. Depending on the chosen exchange and correlation-potential approximation, the calculated z parameter varies slightly and corresponding small but distinctive differences in the calculated band structure and Fermi-surface topology appear. Similarly, topology changes appear when the energy of the mostly unoccupied La 4f states is corrected regarding their experimentally observed position. The calculated results are compared to experimental de Haas-van Alphen data. Our findings show a high sensitivity of the calculated band structure on the pnictide z position and the need for an accurate experimental determination of this parameter at low temperatures, and a particular need for a sophisticated treatment of the La 4f states. Thus, this is not only crucial for the special case of LaFe2P2 studied here, but of importance for the precise determination of the band structure of related 122 materials and La containing compounds in general.
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Affiliation(s)
- T Förster
- Hochfeld-Magnetlabor Dresden (HLD-EMFL) and Würzburg-Dresden Cluster of Excellence ct.qmat, Helmholtz-Zentrum Dresden-Rossendorf, 01328 Dresden, Germany
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8
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Seiro S, Prots Y, Kummer K, Rosner H, Cardoso Gil R, Geibel C. Charge, lattice and magnetism across the valence crossover in EuIr 2Si 2 single crystals. J Phys Condens Matter 2019; 31:305602. [PMID: 30933934 DOI: 10.1088/1361-648x/ab1509] [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: 06/09/2023]
Abstract
We present a detailed study of the temperature evolution of the crystal structure, specific heat, magnetic susceptibility and resistivity of single crystals of the paradigmatic valence-fluctuating compound [Formula: see text]. A comparison to stable-valent isostructural compounds [Formula: see text] (with Eu3+), and [Formula: see text], (with Eu2+) reveals an anomalously large thermal expansion indicative of the lattice softening associated to valence fluctuations. A marked broad peak at temperatures around 65-75 K is observed in specific heat, susceptibility and the derivative of resistivity, as thermal energy becomes large enough to excite Eu into a divalent state, which localizes one f electron and increases scattering of conduction electrons. In addition, the intermediate valence at low temperatures manifests in a moderately renormalized electron mass, with enhanced values of the Sommerfeld coefficient in the specific heat and a Fermi-liquid-like dependence of resistivity at low temperatures. The high residual magnetic susceptibility is mainly ascribed to a Van Vleck contribution. Although the intermediate/fluctuating valence duality is to some extent represented in the interconfiguration fluctuation model commonly used to analyze data on valence-fluctuating systems, we show that this model cannot describe the different physical properties of [Formula: see text] with a single set of parameters.
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Affiliation(s)
- Silvia Seiro
- Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Straße 40, D-01187 Dresden, Germany. IFW-Dresden, Helmholtzstraße 20, D-01069 Dresden, Germany
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9
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Thakur GS, Reuter H, Rosner H, Fecher GH, Felser C, Jansen M. New Ag 8PtO 6: synthesis, crystal structure, physical properties and theoretical analyses. Dalton Trans 2019; 48:5058-5063. [PMID: 30918926 DOI: 10.1039/c8dt05081c] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We report the synthesis, crystal structure, and basic physical properties of Ag8PtO6, which represents the first silver platinum ternary oxide. The crystalline compound was obtained from appropriate mixtures of the binary constituents under alkaline conditions at high oxygen pressure, while applying relatively mild thermal conditions (573 K). Ag8PtO6 crystallizes in a new crystal structure in the triclinic system (P1[combining macron]). The structure consists of slightly distorted, discrete PtO6 octahedra, which are linked via O-Ag-O dumbbells to form a three dimensional framework. It is a diamagnetic semiconductor with a band gap of 0.9 eV. DFT based calculations confirm an electronic ground state that corresponds to a 5d6 6s0 configuration of the Pt atoms, in accordance with the observed diamagnetism.
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Affiliation(s)
- Gohil Singh Thakur
- Max-Planck-Institut für Chemische Physik fester Stoffe, Nöthnitzer Straße 40, 01187 Dresden, Germany
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Schwarz U, Kasinathan D, Bergner C, Hunger J, Meier-Kircher K, Akselrud L, Hanfland M, Mezouar M, Glazyrin K, Stinton GW, Husband R, Rosner H, McMahon MI. Distortions in the cubic primitive high-pressure phases of calcium. J Phys Condens Matter 2019; 31:065401. [PMID: 30523800 DOI: 10.1088/1361-648x/aaf49b] [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] [Indexed: 06/09/2023]
Abstract
The superconductivity in highly compressed calcium involves the occurrence of closely related low-symmetry structural patterns with an exceptionally low coordination number. Earlier theoretical and experimental results are controversial and some findings are inconsistent with our later observations in the pressure range up to 60 GPa. This situation motivated the present concerted computational and experimental re-investigation of the structural arrangement of calcium slightly above the high-pressure limit of the bcc arrangement at low-temperatures. We report here reproducible experimental evidence for a monoclinic distortion (mC4, space group C2/c) of the calcium polymorph previously assigned to the tetragonal β-Sn structure type. In accordance, the enthalpies calculated by electronic band structure calculations show the mC4 phase to be more stable than the undistorted β-Sn type by about 100 meV in the entire phase space. The other low-temperature phase of calcium adopts space group Cmcm (oC4) rather than the earlier assigned Cmmm symmetry. These structural alterations substantially effect the density of states at the Fermi level and, thus, the electronic properties.
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Affiliation(s)
- Ulrich Schwarz
- Max-Planck-Institut für Chemische Physik fester Stoffe, Nöthnitzer Straße 40, D-01187 Dresden, Germany
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11
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Ranjith KM, Klein C, Tsirlin AA, Rosner H, Krellner C, Baenitz M. Magnetic resonance as a local probe for kagomé magnetism in Barlowite Cu 4(OH) 6FBr. Sci Rep 2018; 8:10851. [PMID: 30022078 PMCID: PMC6052016 DOI: 10.1038/s41598-018-29080-8] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [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: 03/28/2018] [Accepted: 07/04/2018] [Indexed: 11/24/2022] Open
Abstract
Temperature- and field-dependent 1H-, 19F-, and 79,81Br-NMR measurements together with zero - field 79,81Br-NQR measurements on polycrystalline samples of barlowite, Cu4(OH)6FBr are conducted to study the magnetism and possible structural distortions on a microscopic level. The temperature dependence of the 79,81Br-NMR spin-lattice relaxation rates 1/T1 indicate a phase transition at TN \documentclass[12pt]{minimal}
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\begin{document}$$\simeq $$\end{document}≃ 15 K which is of magnetic origin, but with an unusually weak slowing down of fluctuations below TN. Moreover, 1/T1T scales linear with the bulk susceptibility which indicates persisting spin fluctuations down to 2 K. Quadupolare resonance (NQR) studies reveal a pair of zero-field NQR- lines associated with the two isotopes of Br with the nuclear spins of I = 3/2. Quadrupole coupling constants of vQ ≃ 28.5 MHz and 24.7 MHz for 79Br- and 81Br-nuclei are determined from Br-NMR and the asymmetry parameter of the electric field gradient was estimated to η ≃ 0.2. The Br-NQR lines are consistent with our findings from Br-NMR and they are relatively broad, even above TN. This broadening and the relative large η value suggests a symmetry reduction at the Br- site reflecting the presence of a local distortion in the lattice. Our density-functional calculations show that the displacements of Cu2 atoms located between the kagome planes do not account for this relatively large η. On the other hand, full structural relaxation, including the deformation of kagome planes, leads to a better agreement with the experiment.
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Affiliation(s)
- K M Ranjith
- Max- Plank- Institute for Chemical Physics of Solids, 01187, Dresden, Germany.
| | - C Klein
- Physikalisches Institut, Goethe-Universitat Frankfurt, 60438, Frankfurt, Germany
| | - A A Tsirlin
- Experimental Physics VI, Center for Electronic Correlations and Magnetism, Institute of Physics, University of Augsburg, 86135, Augsburg, Germany
| | - H Rosner
- Max- Plank- Institute for Chemical Physics of Solids, 01187, Dresden, Germany
| | - C Krellner
- Physikalisches Institut, Goethe-Universitat Frankfurt, 60438, Frankfurt, Germany
| | - M Baenitz
- Max- Plank- Institute for Chemical Physics of Solids, 01187, Dresden, Germany
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12
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Sunko V, Rosner H, Kushwaha P, Khim S, Mazzola F, Bawden L, Clark OJ, Riley JM, Kasinathan D, Haverkort MW, Kim TK, Hoesch M, Fujii J, Vobornik I, Mackenzie AP, King PDC. Maximal Rashba-like spin splitting via kinetic-energy-coupled inversion-symmetry breaking. Nature 2018; 549:492-496. [PMID: 28959958 DOI: 10.1038/nature23898] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2017] [Accepted: 07/26/2017] [Indexed: 11/09/2022]
Abstract
Engineering and enhancing the breaking of inversion symmetry in solids-that is, allowing electrons to differentiate between 'up' and 'down'-is a key goal in condensed-matter physics and materials science because it can be used to stabilize states that are of fundamental interest and also have potential practical applications. Examples include improved ferroelectrics for memory devices and materials that host Majorana zero modes for quantum computing. Although inversion symmetry is naturally broken in several crystalline environments, such as at surfaces and interfaces, maximizing the influence of this effect on the electronic states of interest remains a challenge. Here we present a mechanism for realizing a much larger coupling of inversion-symmetry breaking to itinerant surface electrons than is typically achieved. The key element is a pronounced asymmetry of surface hopping energies-that is, a kinetic-energy-coupled inversion-symmetry breaking, the energy scale of which is a substantial fraction of the bandwidth. Using spin- and angle-resolved photoemission spectroscopy, we demonstrate that such a strong inversion-symmetry breaking, when combined with spin-orbit interactions, can mediate Rashba-like spin splittings that are much larger than would typically be expected. The energy scale of the inversion-symmetry breaking that we achieve is so large that the spin splitting in the CoO2- and RhO2-derived surface states of delafossite oxides becomes controlled by the full atomic spin-orbit coupling of the 3d and 4d transition metals, resulting in some of the largest known Rashba-like spin splittings. The core structural building blocks that facilitate the bandwidth-scaled inversion-symmetry breaking are common to numerous materials. Our findings therefore provide opportunities for creating spin-textured states and suggest routes to interfacial control of inversion-symmetry breaking in designer heterostructures of oxides and other material classes.
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Affiliation(s)
- Veronika Sunko
- SUPA, School of Physics and Astronomy, University of St Andrews, St Andrews KY16 9SS, UK.,Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Straße 40, 01187 Dresden, Germany
| | - H Rosner
- Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Straße 40, 01187 Dresden, Germany
| | - P Kushwaha
- Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Straße 40, 01187 Dresden, Germany
| | - S Khim
- Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Straße 40, 01187 Dresden, Germany
| | - F Mazzola
- SUPA, School of Physics and Astronomy, University of St Andrews, St Andrews KY16 9SS, UK
| | - L Bawden
- SUPA, School of Physics and Astronomy, University of St Andrews, St Andrews KY16 9SS, UK
| | - O J Clark
- SUPA, School of Physics and Astronomy, University of St Andrews, St Andrews KY16 9SS, UK
| | - J M Riley
- SUPA, School of Physics and Astronomy, University of St Andrews, St Andrews KY16 9SS, UK.,Diamond Light Source, Harwell Campus, Didcot OX11 0DE, UK
| | - D Kasinathan
- Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Straße 40, 01187 Dresden, Germany
| | - M W Haverkort
- Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Straße 40, 01187 Dresden, Germany.,Institute for Theoretical Physics, Heidelberg University, Philosophenweg 19, 69120 Heidelberg, Germany
| | - T K Kim
- Diamond Light Source, Harwell Campus, Didcot OX11 0DE, UK
| | - M Hoesch
- Diamond Light Source, Harwell Campus, Didcot OX11 0DE, UK
| | - J Fujii
- Istituto Officina dei Materiali (IOM)-CNR, Laboratorio TASC, Area Science Park, S.S.14, Km 163.5, 34149 Trieste, Italy
| | - I Vobornik
- Istituto Officina dei Materiali (IOM)-CNR, Laboratorio TASC, Area Science Park, S.S.14, Km 163.5, 34149 Trieste, Italy
| | - A P Mackenzie
- SUPA, School of Physics and Astronomy, University of St Andrews, St Andrews KY16 9SS, UK.,Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Straße 40, 01187 Dresden, Germany
| | - P D C King
- SUPA, School of Physics and Astronomy, University of St Andrews, St Andrews KY16 9SS, UK
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13
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Mydeen K, Kasinathan D, Koz C, Rößler S, Rößler UK, Hanfland M, Tsirlin AA, Schwarz U, Wirth S, Rosner H, Nicklas M. Pressure-Induced Ferromagnetism due to an Anisotropic Electronic Topological Transition in Fe_{1.08}Te. Phys Rev Lett 2017; 119:227003. [PMID: 29286759 DOI: 10.1103/physrevlett.119.227003] [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: 03/09/2017] [Indexed: 06/07/2023]
Abstract
A rapid and anisotropic modification of the Fermi-surface shape can be associated with abrupt changes in crystalline lattice geometry or in the magnetic state of a material. We show that such an electronic topological transition is at the basis of the formation of an unusual pressure-induced tetragonal ferromagnetic phase in Fe_{1.08}Te. Around 2 GPa, the orthorhombic and incommensurate antiferromagnetic ground state of Fe_{1.08}Te is transformed upon increasing pressure into a tetragonal ferromagnetic state via a conventional first-order transition. On the other hand, an isostructural transition takes place from the paramagnetic high-temperature state into the ferromagnetic phase as a rare case of a "type-0" transformation with anisotropic properties. Electronic-structure calculations in combination with electrical resistivity, magnetization, and x-ray diffraction experiments show that the electronic system of Fe_{1.08}Te is instable with respect to profound topological transitions that can drive fundamental changes of the lattice anisotropy and the associated magnetic order.
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Affiliation(s)
- K Mydeen
- Max-Planck Institute for Chemical Physics of Solids, Nöthnitzer Straße 40, 01187 Dresden, Germany
| | - D Kasinathan
- Max-Planck Institute for Chemical Physics of Solids, Nöthnitzer Straße 40, 01187 Dresden, Germany
| | - C Koz
- Max-Planck Institute for Chemical Physics of Solids, Nöthnitzer Straße 40, 01187 Dresden, Germany
| | - S Rößler
- Max-Planck Institute for Chemical Physics of Solids, Nöthnitzer Straße 40, 01187 Dresden, Germany
| | - U K Rößler
- Leibniz-Institut für Festkörper- und Werkstoffforschung IFW, Helmholtz Straße 20, 01171 Dresden, Germany
| | - M Hanfland
- ESRF, BP 220, F-38043 Grenoble Cedex 9, France
| | - A A Tsirlin
- Experimental Physics VI, Center for Electronic Correlations and Magnetism, Institute of Physics, University of Augsburg, 86135 Augsburg, Germany
| | - U Schwarz
- Max-Planck Institute for Chemical Physics of Solids, Nöthnitzer Straße 40, 01187 Dresden, Germany
| | - S Wirth
- Max-Planck Institute for Chemical Physics of Solids, Nöthnitzer Straße 40, 01187 Dresden, Germany
| | - H Rosner
- Max-Planck Institute for Chemical Physics of Solids, Nöthnitzer Straße 40, 01187 Dresden, Germany
| | - M Nicklas
- Max-Planck Institute for Chemical Physics of Solids, Nöthnitzer Straße 40, 01187 Dresden, Germany
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14
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Grafe HJ, Nishimoto S, Iakovleva M, Vavilova E, Spillecke L, Alfonsov A, Sturza MI, Wurmehl S, Nojiri H, Rosner H, Richter J, Rößler UK, Drechsler SL, Kataev V, Büchner B. Signatures of a magnetic field-induced unconventional nematic liquid in the frustrated and anisotropic spin-chain cuprate LiCuSbO 4. Sci Rep 2017; 7:6720. [PMID: 28751668 PMCID: PMC5532373 DOI: 10.1038/s41598-017-06525-0] [Citation(s) in RCA: 21] [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: 02/22/2017] [Accepted: 06/14/2017] [Indexed: 11/09/2022] Open
Abstract
Modern theories of quantum magnetism predict exotic multipolar states in weakly interacting strongly frustrated spin-1/2 Heisenberg chains with ferromagnetic nearest neighbor (NN) inchain exchange in high magnetic fields. Experimentally these states remained elusive so far. Here we report strong indications of a magnetic field-induced nematic liquid arising above a field of ~13 T in the edge-sharing chain cuprate LiSbCuO4 ≡ LiCuSbO4. This interpretation is based on the observation of a field induced spin-gap in the measurements of the 7Li NMR spin relaxation rate T 1-1 as well as a contrasting field-dependent power-law behavior of T 1-1 vs. T and is further supported by static magnetization and ESR data. An underlying theoretical microscopic approach favoring a nematic scenario is based essentially on the NN XYZ exchange anisotropy within a model for frustrated spin-1/2 chains and is investigated by the DMRG technique. The employed exchange parameters are justified qualitatively by electronic structure calculations for LiCuSbO4.
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Affiliation(s)
- H-J Grafe
- Leibniz Institute for Solid State and Materials Research IFW-Dresden, D-01171, Dresden, Germany
| | - S Nishimoto
- Leibniz Institute for Solid State and Materials Research IFW-Dresden, D-01171, Dresden, Germany.,Institute for Theoretical Physics, Technical University Dresden, D-01069, Dresden, Germany
| | - M Iakovleva
- Leibniz Institute for Solid State and Materials Research IFW-Dresden, D-01171, Dresden, Germany.,Zavoisky Physical-Technical Institute of the Russian Academy of Sciences, 420029, Kazan, Russia
| | - E Vavilova
- Leibniz Institute for Solid State and Materials Research IFW-Dresden, D-01171, Dresden, Germany.,Zavoisky Physical-Technical Institute of the Russian Academy of Sciences, 420029, Kazan, Russia
| | - L Spillecke
- Leibniz Institute for Solid State and Materials Research IFW-Dresden, D-01171, Dresden, Germany.,Institute for Solid State Physics, Technical University Dresden, D-01069, Dresden, Germany
| | - A Alfonsov
- Leibniz Institute for Solid State and Materials Research IFW-Dresden, D-01171, Dresden, Germany
| | - M-I Sturza
- Leibniz Institute for Solid State and Materials Research IFW-Dresden, D-01171, Dresden, Germany
| | - S Wurmehl
- Leibniz Institute for Solid State and Materials Research IFW-Dresden, D-01171, Dresden, Germany
| | - H Nojiri
- Institute of Materials Research, Tohoku University, 980-8577, Sendai, Japan
| | - H Rosner
- Max-Planck-Institute for Chemical Physics of Solids, Dresden, Germany
| | - J Richter
- Universität Magdeburg, Institut für Theoretische Physik, Magdeburg, Germany
| | - U K Rößler
- Leibniz Institute for Solid State and Materials Research IFW-Dresden, D-01171, Dresden, Germany
| | - S-L Drechsler
- Leibniz Institute for Solid State and Materials Research IFW-Dresden, D-01171, Dresden, Germany
| | - V Kataev
- Leibniz Institute for Solid State and Materials Research IFW-Dresden, D-01171, Dresden, Germany.
| | - B Büchner
- Leibniz Institute for Solid State and Materials Research IFW-Dresden, D-01171, Dresden, Germany.,Institute for Solid State Physics, Technical University Dresden, D-01069, Dresden, Germany
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15
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Lai KT, Komarek AC, Fernández-Díaz MT, Chang PS, Huh S, Rosner H, Kuo CY, Hu Z, Pi TW, Adler P, Ksenofontov V, Tjeng LH, Valldor M. Canted Antiferromagnetism on Rectangular Layers of Fe 2+ in Polymorphic CaFeSeO. Inorg Chem 2017; 56:4271-4279. [PMID: 28345884 DOI: 10.1021/acs.inorgchem.6b02098] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
From stoichiometric amounts of CaO, Fe, and Se, pure powders and single crystals of quaternary [Formula: see text] can be obtained by solid-state reaction and self-flux growth, respectively. The as-synthesized compound exhibits a polymorphic crystal structure, where the two modifications have different stacking sequences of [Formula: see text] layers. The two polymorphs have similar unit cells but different crystal symmetries (Cmc21 and Pnma), of which the former is non-centrosymmetric. Fe is divalent (d6) and high-spin, as proven by X-ray spectroscopy, Mössbauer spectroscopy, and powder neutron diffraction data. The latter two, in combination with magnetic susceptibility and specific heat data, reveal a long-range antiferromagnetic spin order (TN = 160 K) with a minor spin canting. CaFeSeO is an electronic insulator, as confirmed by resistivity measurements and density functional theory calculations. The latter also suggest a relatively small energy difference between the two polymorphs, explaining their intimate intergrowth.
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Affiliation(s)
- Kwing To Lai
- Max Planck Institute for Chemical Physics of Solids , Nöthnitzer Straße 40, 01187 Dresden, Germany
| | | | | | - Pi-Shan Chang
- Max Planck Institute for Chemical Physics of Solids , Nöthnitzer Straße 40, 01187 Dresden, Germany.,Department of Electrophysics, National Chiao Tung University , HsinChu 30100, Taiwan
| | - Sungjoon Huh
- Max Planck Institute for Chemical Physics of Solids , Nöthnitzer Straße 40, 01187 Dresden, Germany.,University of British Colombia , 2329 West Mall, Vancouver, BC V6T 1Z4, Canada
| | - Helge Rosner
- Max Planck Institute for Chemical Physics of Solids , Nöthnitzer Straße 40, 01187 Dresden, Germany
| | - Chang-Yang Kuo
- Max Planck Institute for Chemical Physics of Solids , Nöthnitzer Straße 40, 01187 Dresden, Germany
| | - Zhiwei Hu
- Max Planck Institute for Chemical Physics of Solids , Nöthnitzer Straße 40, 01187 Dresden, Germany
| | - Tun-Wen Pi
- National Synchrotron Radiation Research Centre , Hsinchu 30076, Taiwan
| | - Peter Adler
- Max Planck Institute for Chemical Physics of Solids , Nöthnitzer Straße 40, 01187 Dresden, Germany
| | - Vadim Ksenofontov
- Institut für Anorganische und Analytische Chemie, Johannes Gutenberg-Universität , 55128 Mainz, Germany
| | - Liu Hao Tjeng
- Max Planck Institute for Chemical Physics of Solids , Nöthnitzer Straße 40, 01187 Dresden, Germany
| | - Martin Valldor
- Max Planck Institute for Chemical Physics of Solids , Nöthnitzer Straße 40, 01187 Dresden, Germany
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16
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17
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18
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19
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Steppke A, Zhao L, Barber ME, Scaffidi T, Jerzembeck F, Rosner H, Gibbs AS, Maeno Y, Simon SH, Mackenzie AP, Hicks CW. Strong peak in
T
c
of Sr
2
RuO
4
under uniaxial pressure. Science 2017; 355:355/6321/eaaf9398. [DOI: 10.1126/science.aaf9398] [Citation(s) in RCA: 155] [Impact Index Per Article: 22.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2016] [Accepted: 11/18/2016] [Indexed: 11/02/2022]
Affiliation(s)
- Alexander Steppke
- Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Str. 40, 01187 Dresden, Germany
- Scottish Universities Physics Alliance, School of Physics and Astronomy, University of St. Andrews, St. Andrews KY16 9SS, U.K
| | - Lishan Zhao
- Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Str. 40, 01187 Dresden, Germany
- Scottish Universities Physics Alliance, School of Physics and Astronomy, University of St. Andrews, St. Andrews KY16 9SS, U.K
| | - Mark E. Barber
- Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Str. 40, 01187 Dresden, Germany
- Scottish Universities Physics Alliance, School of Physics and Astronomy, University of St. Andrews, St. Andrews KY16 9SS, U.K
| | - Thomas Scaffidi
- Rudolf Peierls Centre for Theoretical Physics, 1 Keble Road, Oxford OX1 3NP, U.K
| | - Fabian Jerzembeck
- Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Str. 40, 01187 Dresden, Germany
| | - Helge Rosner
- Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Str. 40, 01187 Dresden, Germany
| | - Alexandra S. Gibbs
- Scottish Universities Physics Alliance, School of Physics and Astronomy, University of St. Andrews, St. Andrews KY16 9SS, U.K
- ISIS Facility, Rutherford Appleton Laboratory, Chilton, Didcot OX11 OQX, U.K
| | - Yoshiteru Maeno
- Department of Physics, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan
| | - Steven H. Simon
- Rudolf Peierls Centre for Theoretical Physics, 1 Keble Road, Oxford OX1 3NP, U.K
| | - Andrew P. Mackenzie
- Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Str. 40, 01187 Dresden, Germany
- Scottish Universities Physics Alliance, School of Physics and Astronomy, University of St. Andrews, St. Andrews KY16 9SS, U.K
| | - Clifford W. Hicks
- Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Str. 40, 01187 Dresden, Germany
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20
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Vasylechko L, Stepchuk R, Prots Y, Rosner H. Concentration- and Temperature-Induced Phase Transitions in PrAlO3-SrTiO3 System. Nanoscale Res Lett 2016; 11:17. [PMID: 26759353 PMCID: PMC4710631 DOI: 10.1186/s11671-015-1225-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/16/2015] [Accepted: 12/28/2015] [Indexed: 06/05/2023]
Abstract
Single-phase mixed aluminates-titanates Pr1-x Sr x Al1-x Ti x O3 (x = 0.1, 0.2, 0.3, 0.5, 0.7) with rhombohedral perovskite structure were prepared by solid-state reaction technique at 1823-1873 K. Morphotropic rhombohedral-to-cubic phase transition in Pr1-x Sr x Al1-x Ti x O3 series is predicted to occur at x = 0.88. The temperature-induced structural phase transition R [Formula: see text] с - Pm [Formula: see text] m in Pr0.5Sr0.5Al0.5Ti0.5O3, detected at 930 K by in situ high-temperature X-ray synchrotron powder diffraction, occurs at considerably lower temperature as the corresponding transformation in the parent compound PrAlO3 (1770 K). Such remarkable drop of the transition temperature is explained by gradual decrease of the perovskite structure deformation in the Pr1-x Sr x Al1-x Ti x O3 series with increasing Sr and Ti contents as a consequence of the increasing Goldschmidt tolerance factor. For Pr0.3Sr0.7Al0.3Ti0.7O3 phase, a sequence of the low-temperature phase transformation R [Formula: see text] с - Immb(C2/m) - I4/mcm was detected.
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Affiliation(s)
- Leonid Vasylechko
- Lviv Polytechnic National University, 12 Bandera Street, 79013, Lviv, Ukraine.
| | - Roman Stepchuk
- Lviv Polytechnic National University, 12 Bandera Street, 79013, Lviv, Ukraine.
| | - Yuri Prots
- Max-Planck-Institut für Chemische Physik fester Stoffe, Nöthnitzer Str. 40, 01187, Dresden, Germany.
| | - Helge Rosner
- Max-Planck-Institut für Chemische Physik fester Stoffe, Nöthnitzer Str. 40, 01187, Dresden, Germany.
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21
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Zheng Q, Gumeniuk R, Borrmann H, Schnelle W, Tsirlin AA, Rosner H, Burkhardt U, Reissner M, Grin Y, Leithe-Jasper A. Ternary borides Nb7Fe3B8 and Ta7Fe3B8 with Kagome-type iron framework. Dalton Trans 2016; 45:9590-600. [PMID: 27216270 DOI: 10.1039/c6dt01164k] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Two new ternary borides TM7Fe3B8 (TM = Nb, Ta) were synthesized by high-temperature thermal treatment of samples obtained by arc-melting. This new type of structure with space group P6/mmm, comprises TM slabs containing isolated planar hexagonal [B6] rings and iron centered TM columns in a Kagome type of arrangement. Chemical bonding analysis in Nb7Fe3B8 by means of the electron localizability approach reveals two-center interactions forming the Kagome net of Fe and embedded B, while weaker multicenter bonding present between this net and Nb atoms. Magnetic susceptibility measurements reveal antiferromagnetic order below TN = 240 K for Nb7Fe3B8 and TN = 265 K for Ta7Fe3B8. Small remnant magnetization below 0.01μB per f.u. is observed in the antiferromagnetic state. The bulk nature of the magnetic transistions was confirmed by the hyperfine splitting of the Mössbauer spectra, the sizable anomalies in the specific heat capacity, and the kinks in the resistivity curves. The high-field paramagnetic susceptibilities fitted by the Curie-Weiss law show effective paramagnetic moments μeff≈ 3.1μB/Fe in both compounds. The temperature dependence of the electrical resistivity also reveals metallic character of both compounds. Density functional calculations corroborate the metallic behaviour of both compounds and demonstrate the formation of a sizable local magnetic moment on the Fe-sites. They indicate the presence of both antiferro- and ferrromagnetic interactions.
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Affiliation(s)
- Qiang Zheng
- Max-Planck-Institut für Chemische Physik fester Stoffe, Nöthnitzer Str. 40, 01187 Dresden, Germany.
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22
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Affiliation(s)
- Yu. Grin
- Max-Planck-Institut für Chemische Physik fester Stoffe, Dresden, Germany
| | - M. Armbrüster
- Max-Planck-Institut für Chemische Physik fester Stoffe, Dresden, Germany
| | - A. I. Baranov
- Max-Planck-Institut für Chemische Physik fester Stoffe, Dresden, Germany
| | - K. Finzel
- Max-Planck-Institut für Chemische Physik fester Stoffe, Dresden, Germany
| | - M. Kohout
- Max-Planck-Institut für Chemische Physik fester Stoffe, Dresden, Germany
| | - A. Ormeci
- Max-Planck-Institut für Chemische Physik fester Stoffe, Dresden, Germany
| | - H. Rosner
- Max-Planck-Institut für Chemische Physik fester Stoffe, Dresden, Germany
| | - F. R. Wagner
- Max-Planck-Institut für Chemische Physik fester Stoffe, Dresden, Germany
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23
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Zheng Q, Gumeniuk R, Rosner H, Schnelle W, Prots Y, Burkhardt U, Grin Y, Leithe-Jasper A. Synthesis, crystal structure and properties of the new superconductors TaRuB and NbOsB. J Phys Condens Matter 2015; 27:415701. [PMID: 26418029 DOI: 10.1088/0953-8984/27/41/415701] [Citation(s) in RCA: 9] [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] [Indexed: 06/05/2023]
Abstract
Two new ternary compounds TaRuB and NbOsB were synthesized by arc-melting and annealing at 1500-1850 °C. They crystallize in orthorhombic primitive structures with space group Pbam. Magnetic susceptibility, electrical resistivity, and specific heat measurements reveal bulk superconductivity for metallic TaRuB with a T(c) ≈ 4 K. Electronic structure calculations by DFT methods show that 4d and 5d transition-metal states dominate the density of states (DOS) at the Fermi level E(F) with a pronounced quasi one-dimensional behaviour along the [0 0 1] direction. Comparison of the calculated DOS at E(F) with specific heat data reveals a moderate electron-phonon coupling. Possible small boron vacancies could significantly reduce the DOS at E(F), hence decrease T(c) for samples annealed at higher temperatures. For NbOsB, the DOS(E(F)) is strongly reduced due to an increase of covalent bonding interactions between Os and B. Accordingly, a lower T(c) ≈ 1 K is observed.
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Affiliation(s)
- Qiang Zheng
- Max-Planck-Institut für Chemische Physik fester Stoffe, Nöthnitzer Straße 40, 01187 Dresden, Germany
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24
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Kushwaha P, Sunko V, Moll PJW, Bawden L, Riley JM, Nandi N, Rosner H, Schmidt MP, Arnold F, Hassinger E, Kim TK, Hoesch M, Mackenzie AP, King PDC. Nearly free electrons in a 5d delafossite oxide metal. Sci Adv 2015; 1:e1500692. [PMID: 26601308 PMCID: PMC4646822 DOI: 10.1126/sciadv.1500692] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/28/2015] [Accepted: 08/20/2015] [Indexed: 05/23/2023]
Abstract
Understanding the role of electron correlations in strong spin-orbit transition-metal oxides is key to the realization of numerous exotic phases including spin-orbit-assisted Mott insulators, correlated topological solids, and prospective new high-temperature superconductors. To date, most attention has been focused on the 5d iridium-based oxides. We instead consider the Pt-based delafossite oxide PtCoO2. Our transport measurements, performed on single-crystal samples etched to well-defined geometries using focused ion beam techniques, yield a room temperature resistivity of only 2.1 microhm·cm (μΩ-cm), establishing PtCoO2 as the most conductive oxide known. From angle-resolved photoemission and density functional theory, we show that the underlying Fermi surface is a single cylinder of nearly hexagonal cross-section, with very weak dispersion along k z . Despite being predominantly composed of d-orbital character, the conduction band is remarkably steep, with an average effective mass of only 1.14m e. Moreover, the sharp spectral features observed in photoemission remain well defined with little additional broadening for more than 500 meV below E F, pointing to suppressed electron-electron scattering. Together, our findings establish PtCoO2 as a model nearly-free-electron system in a 5d delafossite transition-metal oxide.
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Affiliation(s)
- Pallavi Kushwaha
- Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Straße 40, 01187 Dresden, Germany
| | - Veronika Sunko
- Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Straße 40, 01187 Dresden, Germany
- Scottish Universities Physics Alliance, School of Physics and Astronomy, University of St. Andrews, St. Andrews, Fife KY16 9SS, UK
| | - Philip J. W. Moll
- Laboratory for Solid State Physics, ETH Zurich, CH-8093 Zurich, Switzerland
| | - Lewis Bawden
- Scottish Universities Physics Alliance, School of Physics and Astronomy, University of St. Andrews, St. Andrews, Fife KY16 9SS, UK
| | - Jonathon M. Riley
- Scottish Universities Physics Alliance, School of Physics and Astronomy, University of St. Andrews, St. Andrews, Fife KY16 9SS, UK
- Diamond Light Source, Harwell Campus, Didcot, Oxfordshire OX11 0DE, UK
| | - Nabhanila Nandi
- Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Straße 40, 01187 Dresden, Germany
| | - Helge Rosner
- Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Straße 40, 01187 Dresden, Germany
| | - Marcus P. Schmidt
- Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Straße 40, 01187 Dresden, Germany
| | - Frank Arnold
- Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Straße 40, 01187 Dresden, Germany
| | - Elena Hassinger
- Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Straße 40, 01187 Dresden, Germany
| | - Timur K. Kim
- Diamond Light Source, Harwell Campus, Didcot, Oxfordshire OX11 0DE, UK
| | - Moritz Hoesch
- Diamond Light Source, Harwell Campus, Didcot, Oxfordshire OX11 0DE, UK
| | - Andrew P. Mackenzie
- Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Straße 40, 01187 Dresden, Germany
- Scottish Universities Physics Alliance, School of Physics and Astronomy, University of St. Andrews, St. Andrews, Fife KY16 9SS, UK
| | - Phil D. C. King
- Scottish Universities Physics Alliance, School of Physics and Astronomy, University of St. Andrews, St. Andrews, Fife KY16 9SS, UK
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Tencé S, Janson O, Krellner C, Rosner H, Schwarz U, Grin Y, Steglich F. CoBi3--the first binary compound of cobalt with bismuth: high-pressure synthesis and superconductivity. J Phys Condens Matter 2014; 26:395701. [PMID: 25204566 DOI: 10.1088/0953-8984/26/39/395701] [Citation(s) in RCA: 6] [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] [Indexed: 06/03/2023]
Abstract
The first compound in the cobalt bismuth system was synthesized by high-pressure high-temperature synthesis at 5 GPa and 450 °C. CoBi3 crystallizes in space group Pnma (no. 62) with lattice parameters of a = 8.8464(7) Å, b = 4.0697(4) Å and c = 11.5604(9) Å adopting a NiBi3-type crystal structure. CoBi3 undergoes a superconducting transition at Tc = 0.48(3) K as evidenced by electrical-resistivity and specific-heat measurements. Based on the anomaly of the specific heat at Tc and considering the estimated electron-phonon coupling, the new Bi-rich compound can be classified as a Bardeen-Cooper-Schrieffer-type superconductor with weak electron-phonon coupling. Density-functional theory calculations disclose a sizable influence of the spin-orbit coupling to the valence states and proximity to a magnetic instability, which accounts for a significantly enhanced Sommerfeld coefficient.
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Affiliation(s)
- S Tencé
- CNRS, ICMCB, UPR 9048, F-33600 Pessac, France. Univ. Bordeaux, ICMCB, UPR 9048, F-33600 Pessac, France
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26
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Maher DP, Wong W, White PF, McKenna R, Rosner H, Shamloo B, Louy C, Wender R, Yumul R, Zhang V. Association of increased postoperative opioid administration with non-small-cell lung cancer recurrence: a retrospective analysis. Br J Anaesth 2014; 113 Suppl 1:i88-94. [PMID: 25009195 DOI: 10.1093/bja/aeu192] [Citation(s) in RCA: 65] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
BACKGROUND Evidence suggests that opioid-sparing anaesthetic techniques might be associated with increased cancer-free postoperative survival. This could be related to suppression of natural killer cells by opioid analgesics in the perioperative period. This retrospective analysis tested the hypothesis that greater opioid use in the postoperative period is associated with a higher incidence of recurrences after surgery for lung cancer. METHODS The medical records of 99 consecutive patients who underwent video-assisted thoracoscopic surgery with lobectomy for Stage I or IIa biopsy-proven non-small-cell lung cancer (NSCLC) were reviewed. Perioperative information including patient characteristics, laboratory data, and surgical, anaesthetic, nursing, and pharmacy reports were collected. Doses of opioids administered intra-operatively and for the first 96 h after operation were converted into equianalgesic doses of oral morphine using a standard conversion table. Data were then compared with the National Cancer Registry's incidence of disease-free survival for 5 yr. RESULTS A total of 99 patients with similar characteristics were included in the final analysis, 73 of whom were NSCLC recurrence-free at 5 yr and 26 had NSCLC recurrence within 5 yr. Total opioid dose during the 96 h postoperative period was 124 (101) mg of morphine equivalents in the cancer-free group and 232 mg (355) mg in the recurrence group (P=0.02). CONCLUSIONS This retrospective analysis suggests an association between increased doses of opioids during the initial 96 h postoperative period with a higher recurrence rate of NSCLC within 5 yr.
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Affiliation(s)
- D P Maher
- Department of Anaesthesiology, Cedars Sinai Medical Center, Los Angeles, CA, USA
| | - W Wong
- Department of Anaesthesiology, Cedars Sinai Medical Center, Los Angeles, CA, USA
| | - P F White
- Department of Anaesthesiology, Cedars Sinai Medical Center, Los Angeles, CA, USA Instituto Ortopedico Rizzoli, University of Bologna, Bologna, Italy
| | - R McKenna
- Department of Anaesthesiology, Cedars Sinai Medical Center, Los Angeles, CA, USA
| | - H Rosner
- Department of Anaesthesiology, Cedars Sinai Medical Center, Los Angeles, CA, USA
| | - B Shamloo
- Department of Anaesthesiology, Cedars Sinai Medical Center, Los Angeles, CA, USA
| | - C Louy
- Department of Anaesthesiology, Cedars Sinai Medical Center, Los Angeles, CA, USA
| | - R Wender
- Department of Anaesthesiology, Cedars Sinai Medical Center, Los Angeles, CA, USA
| | - R Yumul
- Department of Anaesthesiology, Cedars Sinai Medical Center, Los Angeles, CA, USA David Geffen School of Medicine-UCLA, Los Angeles, CA, USA
| | - V Zhang
- Department of Anaesthesiology, Cedars Sinai Medical Center, Los Angeles, CA, USA
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Beekman M, Disch S, Rouvimov S, Kasinathan D, Koepernik K, Rosner H, Zschack P, Neumann WS, Johnson DC. Steuerung größeninduzierter Phasenumwandlungen durch chemisch konzipierte Nanolaminate. Angew Chem Int Ed Engl 2013. [DOI: 10.1002/ange.201305377] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Beekman M, Disch S, Rouvimov S, Kasinathan D, Koepernik K, Rosner H, Zschack P, Neumann WS, Johnson DC. Controlling Size-Induced Phase Transformations Using Chemically Designed Nanolaminates. Angew Chem Int Ed Engl 2013; 52:13211-4. [DOI: 10.1002/anie.201305377] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2013] [Indexed: 11/08/2022]
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29
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Schwarz U, Tencé S, Janson O, Koz C, Krellner C, Burkhardt U, Rosner H, Steglich F, Grin Y. CoBi3: Binäre Cobalt-Bismut-Verbindung und Supraleiter. Angew Chem Int Ed Engl 2013. [DOI: 10.1002/ange.201302397] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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30
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Schwarz U, Tencé S, Janson O, Koz C, Krellner C, Burkhardt U, Rosner H, Steglich F, Grin Y. CoBi3: A Binary Cobalt-Bismuth Compound and Superconductor. Angew Chem Int Ed Engl 2013; 52:9853-7. [DOI: 10.1002/anie.201302397] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2013] [Indexed: 11/10/2022]
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31
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Köhler H, Heller M, Erler W, Müller G, Rosner H, Gräfe U. Effect of ochratoxin A and ochratoxin C on the monocyte and lymphocyte function. Mycotoxin Res 2013; 18 Suppl 2:169-72. [PMID: 23606156 DOI: 10.1007/bf02946089] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
The effect of practically relevant mycotoxin concentrations on functions of immune cells was studied in in vitro experiments. Porcine mononuclear cells were exposed to a crudeAspergillus-ochraceus toxin containing OTA, a HPLC fraction identical with OTC derived from the crude toxin (RE2), as well as pure OTA and OTC in a concentration range from 0.46 to 3000 ng/ml. The influence of mycotoxin exposure on metabolic activity, mitogen induced proliferation, expression of the activation marker CD25 and the cell cycle of lymphocytes and on the formation of free oxygen radicals as well as the production of the cytokines IL-6 and TNF-α by monocytes was determined. Exposure to high concentrations of all mycotoxin preparations lead to non-specific suppression of the immune cell functions, which was related to cytotoxic effects. Low concentrations caused ambivalent reactions, especially on monocyte function. In general, the HPLC fraction RE2 had an up to 100-fold stronger effect than pure OTA. Ochratoxin-induced suppression of lymphocyte proliferation was not abrogated by phenylalanine or aspartame. The results indicate that immunomodulation can be caused by very low mycotoxin concentrations which are not related to clinical symptoms or loss of performance.
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Affiliation(s)
- H Köhler
- Bundesinstitut für gesundheitlichen Verbraucherschutz und Veterinärmedizin, Fachbereich 4, Jena, Naumburger Strasse 96a, D-07743, Jena
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32
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Blaschkowski B, Rosner H, Schnelle W, Schleid T. Sulfidiodide (MSI) der schweren Lanthanoide (M= Gd - Lu): Kristallstrukturen und magnetische Eigenschaften. Z Anorg Allg Chem 2013. [DOI: 10.1002/zaac.201200488] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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33
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Berdonosov PS, Janson O, Olenev AV, Krivovichev SV, Rosner H, Dolgikh VA, Tsirlin AA. Crystal structures and variable magnetism of PbCu2(XO3)2Cl2 with X = Se, Te. Dalton Trans 2013; 42:9547-54. [DOI: 10.1039/c3dt50426c] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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34
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Nicklas M, Kirchner S, Borth R, Gumeniuk R, Schnelle W, Rosner H, Borrmann H, Leithe-Jasper A, Grin Y, Steglich F. Charge-doping-driven evolution of magnetism and non-Fermi-liquid behavior in the filled skutterudite CePt4Ge(12-x)Sb(x). Phys Rev Lett 2012; 109:236405. [PMID: 23368232 DOI: 10.1103/physrevlett.109.236405] [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: 09/14/2012] [Indexed: 06/01/2023]
Abstract
The filled skutterudite compound CePt(4)Ge(12) is situated close to the border between the intermediate valence of Ce and heavy-fermion behavior. Substitution of Ge by Sb drives the system into a strongly correlated and, ultimately, upon further increasing the Sb concentration, an antiferromagnetically ordered state. Our experiments evidence a delicate interplay of emerging Kondo physics and the formation of a local 4f moment. An extended non-Fermi-liquid region, which can be understood in the framework of a Kondo-disorder model, is observed. Band-structure calculations support the conclusion that the physical properties are governed by the interplay of electron supply via Sb substitution and the concomitant volume effects.
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Affiliation(s)
- M Nicklas
- Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Strasse 40, 01187 Dresden, Germany.
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35
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Kuzian RO, Nishimoto S, Drechsler SL, Málek J, Johnston S, van den Brink J, Schmitt M, Rosner H, Matsuda M, Oka K, Yamaguchi H, Ito T. Ca(2)Y(2)Cu(5)O(10): the first frustrated quasi-1D ferromagnet close to criticality. Phys Rev Lett 2012; 109:117207. [PMID: 23005673 DOI: 10.1103/physrevlett.109.117207] [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: 01/30/2012] [Revised: 07/05/2012] [Indexed: 06/01/2023]
Abstract
Ca(2)Y(2)Cu(5)O(10) is built up from edge-shared CuO(4) plaquettes forming spin chains. From inelastic neutron scattering data we extract an in-chain nearest-neighbor exchange J(1)≈-170 K and the frustrating next-neighbor J(2)≈32 K interactions, both significantly larger than previous estimates. The ratio α=|J(2)/J(1)|=0.19±0.01 places the system close to the critical point α(c)=0.25 of the J(1)-J(2) chain but in the 1D ferromagnetic regime. We establish that the vicinity to criticality only marginally affects the dispersion and coherence of the spin-wave-like magnetic excitations but instead results in a dramatic T dependence of high-energy Zhang-Rice singlet excitation intensities.
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Affiliation(s)
- R O Kuzian
- Institute for Theoretical Solid State Physics, IFW Dresden, 01171 Dresden, Germany
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36
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Schwarz U, Wosylus A, Rosner H, Schnelle W, Ormeci A, Meier K, Baranov A, Nicklas M, Leipe S, Müller CJ, Grin Y. Dumbbells of Five-Connected Silicon Atoms and Superconductivity in the Binary Silicides MSi3 (M = Ca, Y, Lu). J Am Chem Soc 2012; 134:13558-61. [DOI: 10.1021/ja3055194] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Ulrich Schwarz
- Max-Planck-Institut für Chemische Physik fester Stoffe, 01187 Dresden, Germany
| | - Aron Wosylus
- Max-Planck-Institut für Chemische Physik fester Stoffe, 01187 Dresden, Germany
| | - Helge Rosner
- Max-Planck-Institut für Chemische Physik fester Stoffe, 01187 Dresden, Germany
| | - Walter Schnelle
- Max-Planck-Institut für Chemische Physik fester Stoffe, 01187 Dresden, Germany
| | - Alim Ormeci
- Max-Planck-Institut für Chemische Physik fester Stoffe, 01187 Dresden, Germany
| | - Katrin Meier
- Max-Planck-Institut für Chemische Physik fester Stoffe, 01187 Dresden, Germany
| | - Alexey Baranov
- Max-Planck-Institut für Chemische Physik fester Stoffe, 01187 Dresden, Germany
| | - Michael Nicklas
- Max-Planck-Institut für Chemische Physik fester Stoffe, 01187 Dresden, Germany
| | - Susann Leipe
- Max-Planck-Institut für Chemische Physik fester Stoffe, 01187 Dresden, Germany
| | - Carola J. Müller
- Max-Planck-Institut für Chemische Physik fester Stoffe, 01187 Dresden, Germany
| | - Yuri Grin
- Max-Planck-Institut für Chemische Physik fester Stoffe, 01187 Dresden, Germany
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37
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Ackerbauer S, Gamza M, Rosner H, Carrillo-Cabrera W, Schnelle W, Senyshyn A, Leithe-Jasper A, Grin Y. Chemical and Physical Properties of MnPtSi. Z Anorg Allg Chem 2012. [DOI: 10.1002/zaac.201204144] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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38
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Ackerbauer SV, Senyshyn A, Borrmann H, Burkhardt U, Ormeci A, Rosner H, Schnelle W, Gamża M, Gumeniuk R, Ramlau R, Bischoff E, Schuster JC, Weitzer F, Leithe-Jasper A, Tjeng LH, Grin Y. Structural Transformation with “Negative Volume Expansion”: Chemical Bonding and Physical Behavior of TiGePt. Chemistry 2012; 18:6272-83. [PMID: 22461109 DOI: 10.1002/chem.201102401] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2011] [Revised: 01/25/2012] [Indexed: 11/07/2022]
Affiliation(s)
- S-V Ackerbauer
- Max-Planck-Institut für Chemische Physik fester Stoffe, Nöthnitzer Straße 40, 01187 Dresden, Germany
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39
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Gumeniuk R, Akselrud L, Kvashnina KO, Schnelle W, Tsirlin AA, Curfs C, Rosner H, Schöneich M, Burkhardt U, Schwarz U, Grin Y, Leithe-Jasper A. Ca3Pt4+xGe13−y and Yb3Pt4Ge13: new derivatives of the Pr3Rh4Sn13 structure type. Dalton Trans 2012; 41:6299-309. [DOI: 10.1039/c2dt30339f] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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40
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Gumeniuk R, Kvashnina KO, Schnelle W, Nicklas M, Borrmann H, Rosner H, Skourski Y, Tsirlin AA, Leithe-Jasper A, Grin Y. Physical properties and valence state of cerium in the filled skutterudite CePt₄Ge₁₂. J Phys Condens Matter 2011; 23:465601. [PMID: 22056917 DOI: 10.1088/0953-8984/23/46/465601] [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] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Electronic, magnetic, and transport properties of the filled platinum-germanium skutterudite CePt₄Ge₁₂ are investigated. High resolution x-ray absorption spectroscopy measurements at the cerium L(III) edge demonstrate that CePt₄Ge₁₂ in this compound has a temperature-independent valence close to three. However, magnetic susceptibility, thermopower, Hall effect, and electronic specific heat reveal a broad maximum at Tmax D 65-80 K, suggesting the presence of valence fluctuations. The Sommerfeld coefficient γ = 105 mJ mol⁻¹ K⁻², deduced from specific heat, indicates moderately enhanced band masses for CePt₄Ge₁₂. We discuss these findings and conclude that CePt₄Ge₁₂ represents a system at the border between intermediate valence (IV) and Kondo lattice behavior. In addition, the lattice specific heat and the thermal conductivity are discussed with respect to the vibrational dynamics of Ce in the [Pt₄Ge₁₂] framework.
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Affiliation(s)
- R Gumeniuk
- Max-Planck-Institut für Chemische Physik fester Stoffe, 01187 Dresden, Germany
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41
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Drechsler SL, Nishimoto S, Kuzian RO, Málek J, Lorenz WEA, Richter J, van den Brink J, Schmitt M, Rosner H. Comment on "Two-spinon and four-spinon continuum in a frustrated ferromagnetic spin-1/2 chain". Phys Rev Lett 2011; 106:219701-219702. [PMID: 21699347 DOI: 10.1103/physrevlett.106.219701] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2010] [Indexed: 05/31/2023]
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42
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Jeschke H, Opahle I, Kandpal H, Valentí R, Das H, Saha-Dasgupta T, Janson O, Rosner H, Brühl A, Wolf B, Lang M, Richter J, Hu S, Wang X, Peters R, Pruschke T, Honecker A. Multistep approach to microscopic models for frustrated quantum magnets: the case of the natural mineral azurite. Phys Rev Lett 2011; 106:217201. [PMID: 21699334 DOI: 10.1103/physrevlett.106.217201] [Citation(s) in RCA: 9] [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: 12/06/2010] [Indexed: 05/31/2023]
Abstract
The natural mineral azurite Cu(3)(CO(3))(2)(OH)(2) is a frustrated magnet displaying unusual and controversially discussed magnetic behavior. Motivated by the lack of a unified description for this system, we perform a theoretical study based on density functional theory as well as state-of-the-art numerical many-body calculations. We propose an effective generalized spin-1/2 diamond chain model which provides a consistent description of experiments: low-temperature magnetization, inelastic neutron scattering, nuclear magnetic resonance measurements, magnetic susceptibility as well as new specific heat measurements. With this study we demonstrate that the balanced combination of first principles with powerful many-body methods successfully describes the behavior of this frustrated material.
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Affiliation(s)
- Harald Jeschke
- Institut für Theoretische Physik, Goethe-Universität Frankfurt am Main, 60438 Frankfurt am Main, Germany
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Haarmann F, Koch K, Jeglič P, Pecher O, Rosner H, Grin Y. NMR Spectroscopy of Intermetallic Compounds: An Experimental and Theoretical Approach to Local Atomic Arrangements in Binary Gallides. Chemistry 2011; 17:7560-8. [PMID: 21590820 DOI: 10.1002/chem.201003486] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2010] [Indexed: 11/07/2022]
Affiliation(s)
- Frank Haarmann
- Institut für Anorganische Chemie, RWTH Aachen, Landoltweg 1, 52074 Aachen, Germany.
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Abakumov AM, D’Hondt H, Rossell MD, Tsirlin AA, Gutnikova O, Filimonov DS, Schnelle W, Rosner H, Hadermann J, Van Tendeloo G, Antipov EV. Coupled anion and cation ordering in Sr3RFe4O10.5 (R=Y, Ho, Dy) anion-deficientperovskites. J SOLID STATE CHEM 2010. [DOI: 10.1016/j.jssc.2010.09.039] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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45
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Wosylus A, Meier K, Prots Y, Schnelle W, Rosner H, Schwarz U, Grin Y. Unusual silicon connectivities in the binary compounds GdSi5, CeSi5, and Ce2Si7. Angew Chem Int Ed Engl 2010; 49:9002-6. [PMID: 20954223 DOI: 10.1002/anie.201003490] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Aron Wosylus
- Max-Planck-Institut für Chemische Physik fester Stoffe, Nöthnitzer Strasse 40, 01187 Dresden, Germany
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Wosylus A, Meier K, Prots Y, Schnelle W, Rosner H, Schwarz U, Grin Y. Ungewöhnliche Siliciumverknüpfungen in den binären Verbindungen GdSi5, CeSi5 und Ce2Si7. Angew Chem Int Ed Engl 2010. [DOI: 10.1002/ange.201003490] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Meier K, Cardoso-Gil R, Schnelle W, Rosner H, Burkhardt U, Schwarz U. Thermal, Magnetic, Electronic, and Superconducting Properties of Rare-Earth Metal Pentagermanides REGe5 (RE = La, Nd, Sm, Gd) and Synthesis of TbGe5. Z Anorg Allg Chem 2010. [DOI: 10.1002/zaac.201000065] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Gumeniuk R, Schmitt M, Schnelle W, Burkhardt U, Rosner H, Leithe-Jasper A. SrPd4B and BaPd4B: New Type of Crystal Structure and Physical Properties. Z Anorg Allg Chem 2010. [DOI: 10.1002/zaac.201000009] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Maisuradze A, Nicklas M, Gumeniuk R, Baines C, Schnelle W, Rosner H, Leithe-Jasper A, Grin Y, Khasanov R. Superfluid density and energy gap function of superconducting PrPt4Ge12. Phys Rev Lett 2009; 103:147002. [PMID: 19905594 DOI: 10.1103/physrevlett.103.147002] [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] [Received: 02/06/2009] [Indexed: 05/28/2023]
Abstract
The filled skutterudite superconductor PrPt4Ge12 was studied in muon-spin rotation (muSR), specific heat, and electrical resistivity experiments. The continuous increase of the superfluid density with decreasing temperature and the dependence of the magnetic penetration depth lambda on the magnetic field obtained by means of muSR, as well as the observation of a T3 dependence of the electronic specific heat indicate the presence of pointlike nodes in the superconducting energy gap. The gap and the specific heat are found to be well described by two models with point nodes, similar to results obtained for the unconventional heavy fermion skutterudite superconductor PrOs4Sb12.
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Affiliation(s)
- A Maisuradze
- Laboratory for Muon Spin Spectroscopy, Paul Scherrer Institut, CH-5232 Villigen PSI, Switzerland.
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Abstract
Abstract
Effects of high pressure on intermetallic compounds are reviewed with regards to structural stability and phase transitions. Changes of bonding properties and electronic structure are examplified by means of the elemental metals caesium and titanium, the latter forming an internal intermetallic compound at high pressures. After a short systematic overview regarding pressure effects, structural transformations in selected classes of intermetallic compounds like Zintl phases and AlB2-type arrangements precedes sections concerning high-pressure synthesis of Laves phases and intermetallic clathrates.
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