Dynamics of a two-dimensional quantum spin liquid: signatures of emergent Majorana fermions and fluxes
Topological states of matter present a wide variety of striking new phenomena. Prominent among these is the fractionalisation of electrons into unusual particles: Majorana fermions [1], Laughlin quasiparticles [2] or magnetic monopoles [3]. Their detection, however, is fundamentally complicated by t...
| Main Authors: | , , , |
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| Format: | Journal article |
| Language: | English |
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American Physical Society
2013
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| _version_ | 1797091794849103872 |
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| author | Knolle, J Kovrizhin, D Chalker, J Moessner, R |
| author_facet | Knolle, J Kovrizhin, D Chalker, J Moessner, R |
| author_sort | Knolle, J |
| collection | OXFORD |
| description | Topological states of matter present a wide variety of striking new phenomena. Prominent among these is the fractionalisation of electrons into unusual particles: Majorana fermions [1], Laughlin quasiparticles [2] or magnetic monopoles [3]. Their detection, however, is fundamentally complicated by the lack of any local order, such as, for example, the magnetisation in a ferromagnet. While there are now several instances of candidate topological spin liquids [4], their identification remains challenging [5]. Here, we provide a complete and exact theoretical study of the dynamical structure factor of a two-dimensional quantum spin liquid in gapless and gapped phases. We show that there are direct signatures - qualitative and quantitative - of the Majorana fermions and gauge fluxes emerging in Kitaev's honeycomb model. These include counterintuitive manifestations of quantum number fractionalisation, such as a neutron scattering response with a gap even in the presence of gapless excitations, and a sharp component despite the fractionalisation of electron spin. Our analysis identifies new varieties of the venerable X-ray edge problem and explores connections to the physics of quantum quenches. |
| first_indexed | 2024-03-07T03:37:37Z |
| format | Journal article |
| id | oxford-uuid:bcd1924b-1926-4552-8fd8-4191e0892d7a |
| institution | University of Oxford |
| language | English |
| last_indexed | 2024-03-07T03:37:37Z |
| publishDate | 2013 |
| publisher | American Physical Society |
| record_format | dspace |
| spelling | oxford-uuid:bcd1924b-1926-4552-8fd8-4191e0892d7a2022-03-27T05:27:16ZDynamics of a two-dimensional quantum spin liquid: signatures of emergent Majorana fermions and fluxesJournal articlehttp://purl.org/coar/resource_type/c_dcae04bcuuid:bcd1924b-1926-4552-8fd8-4191e0892d7aEnglishSymplectic Elements at OxfordAmerican Physical Society2013Knolle, JKovrizhin, DChalker, JMoessner, RTopological states of matter present a wide variety of striking new phenomena. Prominent among these is the fractionalisation of electrons into unusual particles: Majorana fermions [1], Laughlin quasiparticles [2] or magnetic monopoles [3]. Their detection, however, is fundamentally complicated by the lack of any local order, such as, for example, the magnetisation in a ferromagnet. While there are now several instances of candidate topological spin liquids [4], their identification remains challenging [5]. Here, we provide a complete and exact theoretical study of the dynamical structure factor of a two-dimensional quantum spin liquid in gapless and gapped phases. We show that there are direct signatures - qualitative and quantitative - of the Majorana fermions and gauge fluxes emerging in Kitaev's honeycomb model. These include counterintuitive manifestations of quantum number fractionalisation, such as a neutron scattering response with a gap even in the presence of gapless excitations, and a sharp component despite the fractionalisation of electron spin. Our analysis identifies new varieties of the venerable X-ray edge problem and explores connections to the physics of quantum quenches. |
| spellingShingle | Knolle, J Kovrizhin, D Chalker, J Moessner, R Dynamics of a two-dimensional quantum spin liquid: signatures of emergent Majorana fermions and fluxes |
| title | Dynamics of a two-dimensional quantum spin liquid: signatures of
emergent Majorana fermions and fluxes |
| title_full | Dynamics of a two-dimensional quantum spin liquid: signatures of
emergent Majorana fermions and fluxes |
| title_fullStr | Dynamics of a two-dimensional quantum spin liquid: signatures of
emergent Majorana fermions and fluxes |
| title_full_unstemmed | Dynamics of a two-dimensional quantum spin liquid: signatures of
emergent Majorana fermions and fluxes |
| title_short | Dynamics of a two-dimensional quantum spin liquid: signatures of
emergent Majorana fermions and fluxes |
| title_sort | dynamics of a two dimensional quantum spin liquid signatures of emergent majorana fermions and fluxes |
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