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Baez ML, Borzi RA. The 3D Kasteleyn transition in dipolar spin ice: a numerical study with the conserved monopoles algorithm. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2017; 29:055806. [PMID: 27941225 DOI: 10.1088/1361-648x/aa4e6a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
We study the three-dimensional Kasteleyn transition in both nearest neighbours and dipolar spin ice models using an algorithm that conserves the number of excitations. We first limit the interactions range to nearest neighbours to test the method in the presence of a field applied along [Formula: see text], and then focus on the dipolar spin ice model. The effect of dipolar interactions, which is known to be greatly self screened at zero field, is particularly strong near full polarization. It shifts the Kasteleyn transition to lower temperatures, which decreases ≈0.4 K for the parameters corresponding to the best known spin ice materials, [Formula: see text] and [Formula: see text]. This shift implies effective dipolar fields as big as 0.05 T opposing the applied field, and thus favouring the creation of 'strings' of reversed spins. We compare the reduction in the transition temperature with results in previous experiments, and study the phenomenon quantitatively using a simple molecular field approach. Finally, we relate the presence of the effective residual field to the appearance of string-ordered phases at low fields and temperatures, and we check numerically that for fields applied along [Formula: see text] there are only three different stable phases at zero temperature.
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Affiliation(s)
- M L Baez
- Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas (INIFTA), UNLP-CONICET, La Plata, Argentina
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Rehn J, Moessner R. Maxwell electromagnetism as an emergent phenomenon in condensed matter. PHILOSOPHICAL TRANSACTIONS. SERIES A, MATHEMATICAL, PHYSICAL, AND ENGINEERING SCIENCES 2016; 374:rsta.2016.0093. [PMID: 27458263 DOI: 10.1098/rsta.2016.0093] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 04/25/2016] [Indexed: 06/06/2023]
Abstract
The formulation of a complete theory of classical electromagnetism by Maxwell is one of the milestones of science. The capacity of many-body systems to provide emergent mini-universes with vacua quite distinct from the one we inhabit was only recognized much later. Here, we provide an account of how simple systems of localized spins manage to emulate Maxwell electromagnetism in their low-energy behaviour. They are much less constrained by symmetry considerations than the relativistically invariant electromagnetic vacuum, as their substrate provides a non-relativistic background with even translational invariance broken. They can exhibit rich behaviour not encountered in conventional electromagnetism. This includes the existence of magnetic monopole excitations arising from fractionalization of magnetic dipoles; as well as the capacity of disorder, by generating defects on the lattice scale, to produce novel physics, as exemplified by topological spin glassiness or random Coulomb magnetism.This article is part of the themed issue 'Unifying physics and technology in light of Maxwell's equations'.
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Affiliation(s)
- J Rehn
- Max Planck Institut für Physik komplexer Systeme, 01187 Dresden, Germany
| | - R Moessner
- Max Planck Institut für Physik komplexer Systeme, 01187 Dresden, Germany
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Fenner LA, Dee AA, Wills AS. Non-collinearity and spin frustration in the itinerant kagome ferromagnet Fe(3)Sn(2). JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2009; 21:452202. [PMID: 21694002 DOI: 10.1088/0953-8984/21/45/452202] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Frustrated itinerant ferromagnets, with non-collinear static spin structures, are an exciting class of material as their spin chirality can introduce a Berry phase in the electronic scattering and lead to exotic electronic phenomena such as the anomalous Hall effect (AHE). This study presents a reexamination of the magnetic properties of Fe(3)Sn(2), a metallic ferromagnet, based on the two-dimensional kagome bilayer structure. Previously thought of as a conventional ferromagnet, we show using a combination of SQUID (superconducting quantum interference device) measurements, symmetry analysis and powder neutron diffraction that Fe(3)Sn(2) is a frustrated ferromagnet with a temperature-dependent non-collinear spin structure. The complexity of the magnetic interactions is further evidenced by a re-entrant spin glass transition ([Formula: see text] K) at temperatures far below the main ferromagnetic transition (T(C) = 640 K). Fe(3)Sn(2) therefore provides a rare example of a frustrated itinerant ferromagnet. Further, as well as being of great fundamental interest our studies highlight the potential of Fe(3)Sn(2) for practical application in spintronics technology, as the AHE arising from the ferromagnetism in this material is expected to be enhanced by the coupling between the conduction electrons and the non-trivial magnetic structure over an exceptionally wide temperature range.
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Affiliation(s)
- L A Fenner
- Chemistry Department, UCL, 20 Gordon Street, London WC1H 0AJ, UK
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Morris DJP, Tennant DA, Grigera SA, Klemke B, Castelnovo C, Moessner R, Czternasty C, Meissner M, Rule KC, Hoffmann JU, Kiefer K, Gerischer S, Slobinsky D, Perry RS. Dirac Strings and Magnetic Monopoles in the Spin Ice Dy
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7. Science 2009; 326:411-4. [DOI: 10.1126/science.1178868] [Citation(s) in RCA: 447] [Impact Index Per Article: 29.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Affiliation(s)
- D. J. P. Morris
- Helmholtz-Zentrum Berlin für Materialien und Energie, Glienicker Str. 100, D-14109 Berlin, Germany
| | - D. A. Tennant
- Helmholtz-Zentrum Berlin für Materialien und Energie, Glienicker Str. 100, D-14109 Berlin, Germany
- Institut für Festkörperphysik, Technische Universität Berlin, Hardenbergstr. 36, D-10623 Berlin, Germany
| | - S. A. Grigera
- School of Physics and Astronomy, North Haugh, St. Andrews, Fife KY15 9SS, UK
- Instituto de Física de Líquidos y Sistemas Biológicos, CONICET, UNLP, La Plata, Argentina
| | - B. Klemke
- Helmholtz-Zentrum Berlin für Materialien und Energie, Glienicker Str. 100, D-14109 Berlin, Germany
- Institut für Festkörperphysik, Technische Universität Berlin, Hardenbergstr. 36, D-10623 Berlin, Germany
| | - C. Castelnovo
- Rudolf Peierls Centre for Theoretical Physics, 1 Keble Road, Oxford OX1 3NP, UK
| | - R. Moessner
- Max-Planck-Institut für Physik Komplexer Systeme, Nöthnitzer Str. 38, D-01187 Dresden, Germany
| | - C. Czternasty
- Helmholtz-Zentrum Berlin für Materialien und Energie, Glienicker Str. 100, D-14109 Berlin, Germany
| | - M. Meissner
- Helmholtz-Zentrum Berlin für Materialien und Energie, Glienicker Str. 100, D-14109 Berlin, Germany
| | - K. C. Rule
- Helmholtz-Zentrum Berlin für Materialien und Energie, Glienicker Str. 100, D-14109 Berlin, Germany
| | - J.-U. Hoffmann
- Helmholtz-Zentrum Berlin für Materialien und Energie, Glienicker Str. 100, D-14109 Berlin, Germany
| | - K. Kiefer
- Helmholtz-Zentrum Berlin für Materialien und Energie, Glienicker Str. 100, D-14109 Berlin, Germany
| | - S. Gerischer
- Helmholtz-Zentrum Berlin für Materialien und Energie, Glienicker Str. 100, D-14109 Berlin, Germany
| | - D. Slobinsky
- School of Physics and Astronomy, North Haugh, St. Andrews, Fife KY15 9SS, UK
| | - R. S. Perry
- School of Physics, University of Edinburgh, Mayfield Road, Edinburgh EH9 3JZ, UK
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