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Tian W, Fishman RS, Cao HB, Sala G, Pajerowski DM, Garlea VO, Hong T, Daemen LL, Cheng YQ, Fernandez-Baca JA. IInvestigating the nature of the magnetoelectric coupling in molecular (ND4)2[FeCl5(D2O)] via neutron scattering studies. Acta Crystallogr A Found Adv 2021. [DOI: 10.1107/s0108767321094599] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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2
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Zhang H, Zhao Z, Gautreau D, Raczkowski M, Saha A, Garlea VO, Cao H, Hong T, Jeschke HO, Mahanti SD, Birol T, Assaad FF, Ke X. Coexistence and Interaction of Spinons and Magnons in an Antiferromagnet with Alternating Antiferromagnetic and Ferromagnetic Quantum Spin Chains. Phys Rev Lett 2020; 125:037204. [PMID: 32745383 DOI: 10.1103/physrevlett.125.037204] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/2020] [Accepted: 06/18/2020] [Indexed: 06/11/2023]
Abstract
In conventional quasi-one-dimensional antiferromagnets with quantum spins, magnetic excitations are carried by either magnons or spinons in different energy regimes: they do not coexist independently, nor could they interact with each other. In this Letter, by combining inelastic neutron scattering, quantum Monte Carlo simulations, and random phase approximation calculations, we report the discovery and discuss the physics of the coexistence of magnons and spinons and their interactions in Botallackite-Cu_{2}(OH)_{3}Br. This is a unique quantum antiferromagnet consisting of alternating ferromagnetic and antiferromagnetic spin-1/2 chains with weak interchain couplings. Our study presents a new paradigm where one can study the interaction between two different types of magnetic quasiparticles: magnons and spinons.
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Affiliation(s)
- H Zhang
- Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824, USA
| | - Z Zhao
- State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, Fujian 350002, People's Republic of China
| | - D Gautreau
- Department of Chemical Engineering and Materials Science, University of Minnesota, Minnesota 55455, USA
| | - M Raczkowski
- Institut für Theoretische Physik und Astrophysik, Universität Würzburg, 97074 Würzburg, Germany
| | - A Saha
- Department of Chemical Engineering and Materials Science, University of Minnesota, Minnesota 55455, USA
| | - V O Garlea
- Neutron Scattering Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - H Cao
- Neutron Scattering Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - T Hong
- Neutron Scattering Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - H O Jeschke
- Research Institute for Interdisciplinary Science, Okayama University, Okayama 700-8530, Japan
| | - Subhendra D Mahanti
- Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824, USA
| | - T Birol
- Department of Chemical Engineering and Materials Science, University of Minnesota, Minnesota 55455, USA
| | - F F Assaad
- Institut für Theoretische Physik und Astrophysik, Universität Würzburg, 97074 Würzburg, Germany
- Würzburg-Dresden Cluster of Excellence ct.qmat, Am Hubland, D-97074 Würzburg, Germany
| | - X Ke
- Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824, USA
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Manley ME, Hellman O, Shulumba N, May AF, Stonaha PJ, Lynn JW, Garlea VO, Alatas A, Hermann RP, Budai JD, Wang H, Sales BC, Minnich AJ. Intrinsic anharmonic localization in thermoelectric PbSe. Nat Commun 2019; 10:1928. [PMID: 31028271 PMCID: PMC6486597 DOI: 10.1038/s41467-019-09921-4] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2018] [Accepted: 04/05/2019] [Indexed: 11/22/2022] Open
Abstract
Lead chalcogenides have exceptional thermoelectric properties and intriguing anharmonic lattice dynamics underlying their low thermal conductivities. An ideal material for thermoelectric efficiency is the phonon glass-electron crystal, which drives research on strategies to scatter or localize phonons while minimally disrupting electronic-transport. Anharmonicity can potentially do both, even in perfect crystals, and simulations suggest that PbSe is anharmonic enough to support intrinsic localized modes that halt transport. Here, we experimentally observe high-temperature localization in PbSe using neutron scattering but find that localization is not limited to isolated modes - zero group velocity develops for a significant section of the transverse optic phonon on heating above a transition in the anharmonic dynamics. Arrest of the optic phonon propagation coincides with unusual sharpening of the longitudinal acoustic mode due to a loss of phase space for scattering. Our study shows how nonlinear physics beyond conventional anharmonic perturbations can fundamentally alter vibrational transport properties.
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Affiliation(s)
- M E Manley
- Material Science and Technology Division, Oak Ridge National Lab, Oak Ridge, TN, 37831, USA.
| | - O Hellman
- Division of Engineering and Applied Science, California Institute of Technology, Pasadena, CA, 91125, USA
| | - N Shulumba
- Division of Engineering and Applied Science, California Institute of Technology, Pasadena, CA, 91125, USA
| | - A F May
- Material Science and Technology Division, Oak Ridge National Lab, Oak Ridge, TN, 37831, USA
| | - P J Stonaha
- Material Science and Technology Division, Oak Ridge National Lab, Oak Ridge, TN, 37831, USA
| | - J W Lynn
- NIST Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, MD, 20899, USA
| | - V O Garlea
- Neutron Scattering Division, Oak Ridge National Lab, Oak Ridge, TN, 37831, USA
| | - A Alatas
- Advanced Photon Source, Argonne National Laboratory, Argonne, IL, 64039, USA
| | - R P Hermann
- Material Science and Technology Division, Oak Ridge National Lab, Oak Ridge, TN, 37831, USA
| | - J D Budai
- Material Science and Technology Division, Oak Ridge National Lab, Oak Ridge, TN, 37831, USA
| | - H Wang
- Material Science and Technology Division, Oak Ridge National Lab, Oak Ridge, TN, 37831, USA
| | - B C Sales
- Material Science and Technology Division, Oak Ridge National Lab, Oak Ridge, TN, 37831, USA
| | - A J Minnich
- Division of Engineering and Applied Science, California Institute of Technology, Pasadena, CA, 91125, USA.
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4
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Sinclair R, Cao HB, Garlea VO, Lee M, Choi ES, Dun ZL, Dong S, Dagotto E, Zhou HD. Canted magnetic ground state of quarter-doped manganites R 0.75Ca 0.25MnO 3 (R = Y, Tb, Dy, Ho, and Er). J Phys Condens Matter 2017; 29:065802. [PMID: 28002058 DOI: 10.1088/1361-648x/aa4de1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Polycrystalline samples of the quarter-doped manganites R 0.75Ca0.25MnO3 (R = Y, Tb, Dy, Ho, and Er) were studied by x-ray diffraction and AC/DC susceptibility measurements. All five samples are orthorhombic and exhibit similar magnetic properties: enhanced ferromagnetism below T 1 (∼80 K) and a spin glass (SG) state below T SG (∼30 K). With increasing R 3+ ionic size, both T 1 and T SG generally increase. The single crystal neutron diffraction results on Tb0.75Ca0.25MnO3 revealed that the SG state is mainly composed of a short-range ordered version of a novel canted (i.e. noncollinear) antiferromagnetic spin state. Furthermore, calculations based on the double exchange model for quarter-doped manganites reveal that this new magnetic phase provides a transition state between the ferromagnetic state and the theoretically predicted spin-orthogonal stripe phase.
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Affiliation(s)
- R Sinclair
- Department of Physics and Astronomy, University of Tennessee, Knoxville, TN 37996-1200, USA
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5
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Rau JG, Wu LS, May AF, Poudel L, Winn B, Garlea VO, Huq A, Whitfield P, Taylor AE, Lumsden MD, Gingras MJP, Christianson AD. Anisotropic Exchange within Decoupled Tetrahedra in the Quantum Breathing Pyrochlore Ba_{3}Yb_{2}Zn_{5}O_{11}. Phys Rev Lett 2016; 116:257204. [PMID: 27391749 DOI: 10.1103/physrevlett.116.257204] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2016] [Indexed: 06/06/2023]
Abstract
The low energy spin excitation spectrum of the breathing pyrochlore Ba_{3}Yb_{2}Zn_{5}O_{11} has been investigated with inelastic neutron scattering. Several nearly resolution limited modes with no observable dispersion are observed at 250 mK while, at elevated temperatures, transitions between excited levels become visible. To gain deeper insight, a theoretical model of isolated Yb^{3+} tetrahedra parametrized by four anisotropic exchange constants is constructed. The model reproduces the inelastic neutron scattering data, specific heat, and magnetic susceptibility with high fidelity. The fitted exchange parameters reveal a Heisenberg antiferromagnet with a very large Dzyaloshinskii-Moriya interaction. Using this model, we predict the appearance of an unusual octupolar paramagnet at low temperatures and speculate on the development of intertetrahedron correlations.
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Affiliation(s)
- J G Rau
- Department of Physics and Astronomy, University of Waterloo, Ontario N2L 3G1, Canada
| | - L S Wu
- Quantum Condensed Matter Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - A F May
- Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - L Poudel
- Quantum Condensed Matter Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
- Department of Physics and Astronomy, University of Tennessee, Knoxville, Tennessee 37966, USA
| | - B Winn
- Quantum Condensed Matter Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - V O Garlea
- Quantum Condensed Matter Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - A Huq
- Chemical and Engineering Materials Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - P Whitfield
- Chemical and Engineering Materials Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - A E Taylor
- Quantum Condensed Matter Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - M D Lumsden
- Quantum Condensed Matter Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - M J P Gingras
- Department of Physics and Astronomy, University of Waterloo, Ontario N2L 3G1, Canada
- Perimeter Institute for Theoretical Physics, Waterloo, Ontario N2L 2Y5, Canada
- Canadian Institute for Advanced Research, 180 Dundas Street West, Suite 1400, Toronto, Ontario M5G 1Z8, Canada
| | - A D Christianson
- Quantum Condensed Matter Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
- Department of Physics and Astronomy, University of Tennessee, Knoxville, Tennessee 37966, USA
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Smith GJ, Simonson JW, Orvis T, Marques C, Grose JE, Kistner-Morris JJ, Wu L, Cho K, Kim H, Tanatar MA, Garlea VO, Prozorov R, Zhu Y, Aronson MC. Intrinsic nanostructure in Zr2-xFe4Si16-y(x = 0.81, y = 6.06). J Phys Condens Matter 2014; 26:376002. [PMID: 25164321 DOI: 10.1088/0953-8984/26/37/376002] [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: 06/03/2023]
Abstract
We present a study of the crystal structure and physical properties of single crystals of a new Fe-based ternary compound, Zr2-xFe4Si16-y(x = 0.81, y = 6.06). Zr1.19Fe4Si9.94 is a layered compound, where stoichiometric β-FeSi2-derived slabs are separated by Zr-Si planes with substantial numbers of vacancies. High resolution transmission electron microscopy (HRTEM) experiments show that these Zr-Si layers consist of 3.5 nm domains where the Zr and Si vacancies are ordered within a supercell sixteen times the volume of the stoichiometric cell. Within these domains, the occupancies of the Zr and Si sites obey symmetry rules that permit only certain compositions, none of which by themselves reproduce the average composition found in x-ray diffraction experiments. Magnetic susceptibility and magnetization measurements reveal a small but appreciable number of magnetic moments that remain freely fluctuating to 1.8 K, while neutron diffraction confirms the absence of bulk magnetic order with a moment of 0.2μB or larger down to 1.5 K. Electrical resistivity measurements find that Zr1.19Fe4Si9.94 is metallic, and the modest value of the Sommerfeld coefficient of the specific heat γ = C/T suggests that quasi-particle masses are not particularly strongly enhanced. The onset of superconductivity at Tc ≃ 6 K results in a partial resistive transition and a small Meissner signal, although a bulk-like transition is found in the specific heat. Sharp peaks in the ac susceptibility signal the interplay of the normal skin depth and the London penetration depth, typical of a system in which nano-sized superconducting grains are separated by a non-superconducting host. Ultra low field differential magnetic susceptibility measurements reveal the presence of a surprisingly large number of trace magnetic and superconducting phases, suggesting that the Zr-Fe-Si ternary system could be a potentially rich source of new bulk superconductors.
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Affiliation(s)
- G J Smith
- Department of Physics and Astronomy, Stony Brook University, Stony Brook, NY 11794-3800, USA
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Roudebush JH, Andersen NH, Ramlau R, Garlea VO, Toft-Petersen R, Norby P, Schneider R, Hay JN, Cava RJ. Structure and Magnetic Properties of Cu3Ni2SbO6 and Cu3Co2SbO6 Delafossites with Honeycomb Lattices. Inorg Chem 2013; 52:6083-95. [DOI: 10.1021/ic400415h] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- J. H. Roudebush
- Department of Chemistry, Princeton University, Washington Road, Princeton, New Jersey 08544, United States
| | - N. H. Andersen
- Department of Physics, Technical University of Denmark, DTU Risø Campus,
Frederiksborgvej 399, Building 108-121-129-228, DK-4000 Roskilde,
Denmark
| | - R. Ramlau
- Max Planck Institute for Chemical Physics of Solids, Nöthnitzer
Strasse 40, D-01187 Dresden, Germany
| | - V. O. Garlea
- Quantum Condensed Matter Division, Oak Ridge National Laboratory, P.O. Box 2008, Oak Ridge, Tennessee 37831,
United States
| | - R. Toft-Petersen
- Helmholtz Zentrum Berlin for Materials and Energy,
Kekuléstrasse 5, D-14109 Berlin, Germany
| | - P. Norby
- Materials Research Division, Technical University of Denmark, AFM-228, Frederiksborgvej 399,
P.O. Box 49, DK-4000 Roskilde, Denmark
| | - R. Schneider
- Laboratory for Electron Microscopy, Karlsruhe Institute of Technology, Engesserstrasse
7, Geb. 30.22 (Physik Flachbau), 2. OG, Zimmer 228, D-76128 Karlsruhe,
Germany
| | - J. N. Hay
- Department of Chemistry, Princeton University, Washington Road, Princeton, New Jersey 08544, United States
| | - R. J. Cava
- Department of Chemistry, Princeton University, Washington Road, Princeton, New Jersey 08544, United States
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Klein H, Garlea VO, Darie C, Bordet P. The structure of nano-twinned rhombohedric YCuO 2.66solved by electron crystallography. Acta Crystallogr A 2012. [DOI: 10.1107/s0108767312098820] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
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9
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Calder S, Garlea VO, McMorrow DF, Lumsden MD, Stone MB, Lang JC, Kim JW, Schlueter JA, Shi YG, Yamaura K, Sun YS, Tsujimoto Y, Christianson AD. Magnetically driven metal-insulator transition in NaOsO3. Phys Rev Lett 2012; 108:257209. [PMID: 23004655 DOI: 10.1103/physrevlett.108.257209] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2012] [Revised: 03/21/2012] [Indexed: 05/13/2023]
Abstract
The metal-insulator transition (MIT) is one of the most dramatic manifestations of electron correlations in materials. Various mechanisms producing MITs have been extensively considered, including the Mott (electron localization via Coulomb repulsion), Anderson (localization via disorder), and Peierls (localization via distortion of a periodic one-dimensional lattice) mechanisms. One additional route to a MIT proposed by Slater, in which long-range magnetic order in a three dimensional system drives the MIT, has received relatively little attention. Using neutron and x-ray scattering we show that the MIT in NaOsO(3) is coincident with the onset of long-range commensurate three dimensional magnetic order. While candidate materials have been suggested, our experimental methodology allows the first definitive demonstration of the long predicted Slater MIT.
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Affiliation(s)
- S Calder
- Quantum Condensed Matter Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA.
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10
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Vaknin D, Garlea VO, Demmel F, Mamontov E, Nojiri H, Martin C, Chiorescu I, Qiu Y, Kögerler P, Fielden J, Engelhardt L, Rainey C, Luban M. Level crossings and zero-field splitting in the {Cr8}-cubane spin cluster studied using inelastic neutron scattering and magnetization. J Phys Condens Matter 2010; 22:466001. [PMID: 21403379 DOI: 10.1088/0953-8984/22/46/466001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Inelastic neutron scattering (INS) in variable magnetic field and high-field magnetization measurements in the millikelvin temperature range were performed to gain insight into the low-energy magnetic excitation spectrum and the field-induced level crossings in the molecular spin cluster {Cr(8)}-cubane. These complementary techniques provide consistent estimates of the lowest level-crossing field. The overall features of the experimental data are explained using an isotropic Heisenberg model, based on three distinct exchange interactions linking the eight Cr(III) paramagnetic centers (spins s = 3/2), that is supplemented with a relatively large molecular magnetic anisotropy term for the lowest S = 1 multiplet. It is noted that the existence of the anisotropy is clearly evident from the magnetic field dependence of the excitations in the INS measurements, while the magnetization measurements are not sensitive to its effects.
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Affiliation(s)
- D Vaknin
- Ames Laboratory, Department of Physics and Astronomy, Iowa State University, Ames, IA 50011, USA.
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11
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Zheludev A, Garlea VO, Regnault LP, Manaka H, Tsvelik A, Chung JH. Extended universal finite-T renormalization of excitations in a class of one-dimensional quantum magnets. Phys Rev Lett 2008; 100:157204. [PMID: 18518148 DOI: 10.1103/physrevlett.100.157204] [Citation(s) in RCA: 2] [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: 11/26/2007] [Revised: 02/13/2008] [Indexed: 05/26/2023]
Abstract
Temperature dependencies of gap energies and magnon lifetimes are measured in the quasi-one-dimensional S=1/2 gapped quantum magnets (CH3)(2)CHNH(3)CuCL(3) (IPA-CuCl(3), where IPA denotes isopropyl ammonium) and Cu(2)Cl(4).D(8)C(4)SO(2) (Sul-Cu(2)Cl(4)) using inelastic neutron scattering. The results are compared to those found in literature for S=1 Haldane spin chain materials and to theoretical calculations for the O(3)- and O(N)- quantum nonlinear sigma-models. It is found that when the T=0 energy gap Delta is used as the temperature scale, all experimental and theoretical curves are identical to within system-dependent but temperature-independent scaling factors of the order of unity. This quasi-universality extends over a surprising broad T range, at least up to kappaT approximately 1.5 Delta.
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Affiliation(s)
- A Zheludev
- Neutron Scattering Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA.
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Garlea VO, Jin R, Mandrus D, Roessli B, Huang Q, Miller M, Schultz AJ, Nagler SE. Magnetic and orbital ordering in the spinel MnV2O4. Phys Rev Lett 2008; 100:066404. [PMID: 18352495 DOI: 10.1103/physrevlett.100.066404] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/2007] [Indexed: 05/26/2023]
Abstract
Neutron inelastic scattering and diffraction techniques have been used to study the MnV2O4 spinel system. Our measurements show the existence of two transitions to long-range ordered ferrimagnetic states, the first collinear and the second noncollinear. The lower temperature transition, characterized by development of antiferromagnetic components in the basal plane, is accompanied by a tetragonal distortion and the appearance of a gap in the magnetic excitation spectrum. The low-temperature noncollinear magnetic structure has been definitively resolved. Taken together, the crystal and magnetic structures indicate a staggered ordering of the V d orbitals. The anisotropy gap is a consequence of unquenched V orbital angular momentum.
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Affiliation(s)
- V O Garlea
- Neutron Scattering Science Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA.
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13
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Garlea VO, Zheludev A, Regnault LP, Chung JH, Qiu Y, Boehm M, Habicht K, Meissner M. Excitations in a four-leg antiferromagnetic Heisenberg spin tube. Phys Rev Lett 2008; 100:037206. [PMID: 18233035 DOI: 10.1103/physrevlett.100.037206] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/03/2007] [Indexed: 05/25/2023]
Abstract
Inelastic neutron scattering is used to investigate magnetic excitations in the quasi-one-dimensional quantum spin-liquid system Cu(2)Cl(4).D(8)C(4)SO(2). Contrary to previously conjectured models that relied on bond-alternating nearest-neighbor interactions in the spin chains, the dominant interactions are actually next-nearest-neighbor in-chain antiferromagnetic couplings. The appropriate Heisenberg Hamiltonian is equivalent to that of a S=1/2 4-leg spin-tube with almost perfect one dimensionality and no bond alternation. A partial geometric frustration of rung interactions induces a small incommensurability of short-range spin correlations.
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Affiliation(s)
- V O Garlea
- Neutron Scattering Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA.
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14
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Garlea VO, Zheludev A, Masuda T, Manaka H, Regnault LP, Ressouche E, Grenier B, Chung JH, Qiu Y, Habicht K, Kiefer K, Boehm M. Excitations from a Bose-Einstein condensate of magnons in coupled spin ladders. Phys Rev Lett 2007; 98:167202. [PMID: 17501456 DOI: 10.1103/physrevlett.98.167202] [Citation(s) in RCA: 2] [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: 10/24/2006] [Revised: 01/29/2007] [Indexed: 05/15/2023]
Abstract
The weakly coupled quasi-one-dimensional spin ladder compound (CH3)2CHNH3CuCl3 is studied by neutron scattering in magnetic fields exceeding the critical field of Bose-Einstein condensation of magnons. Commensurate long-range order and the associated Goldstone mode are detected and found to be similar to those in reference to spin-dimer materials. However, for the upper two massive magnon branches, the observed behavior is totally different, culminating in a drastic collapse of excitation bandwidth beyond the transition point.
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Affiliation(s)
- V O Garlea
- Neutron Scattering Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831-6393, USA
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