Evidence for unidirectional nematic bond ordering in FeSe
The lifting of $d_{xz}$-$d_{yz}$ orbital degeneracy is often considered a hallmark of the nematic phase of Fe-based superconductors, including FeSe, but its origin is not yet understood. Here we report a high resolution Angle-Resolved Photoemission Spectroscopy study of single crystals of FeSe, acco...
| Main Authors: | , , , , , , |
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| Format: | Journal article |
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American Physical Society
2016
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| _version_ | 1797053593500516352 |
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| author | Watson, M Kim, T Rhodes, L Eschrig, M Hoesch, M Haghighirad, A Coldea, A |
| author_facet | Watson, M Kim, T Rhodes, L Eschrig, M Hoesch, M Haghighirad, A Coldea, A |
| author_sort | Watson, M |
| collection | OXFORD |
| description | The lifting of $d_{xz}$-$d_{yz}$ orbital degeneracy is often considered a hallmark of the nematic phase of Fe-based superconductors, including FeSe, but its origin is not yet understood. Here we report a high resolution Angle-Resolved Photoemission Spectroscopy study of single crystals of FeSe, accounting for the photon-energy dependence and making a detailed analysis of the temperature dependence. We find that the hole pocket undergoes a fourfold-symmetry-breaking distortion in the nematic phase below 90~K, but in contrast the changes to the electron pockets do not require fourfold symmetry-breaking. Instead, there is an additional separation of the existing $d_{xy}$ and $d_{xz/yz}$ bands - which themselves are not split within resolution. These observations lead us to propose a new scenario of "unidirectional nematic bond ordering" to describe the low-temperature electronic structure of FeSe, supported by a good agreement with 10-orbital tight binding model calculations. |
| first_indexed | 2024-03-06T18:45:50Z |
| format | Journal article |
| id | oxford-uuid:0e7b85fd-ba41-4dbb-be59-496c347098ea |
| institution | University of Oxford |
| last_indexed | 2024-03-06T18:45:50Z |
| publishDate | 2016 |
| publisher | American Physical Society |
| record_format | dspace |
| spelling | oxford-uuid:0e7b85fd-ba41-4dbb-be59-496c347098ea2022-03-26T09:46:10ZEvidence for unidirectional nematic bond ordering in FeSeJournal articlehttp://purl.org/coar/resource_type/c_dcae04bcuuid:0e7b85fd-ba41-4dbb-be59-496c347098eaSymplectic Elements at OxfordAmerican Physical Society2016Watson, MKim, TRhodes, LEschrig, MHoesch, MHaghighirad, AColdea, AThe lifting of $d_{xz}$-$d_{yz}$ orbital degeneracy is often considered a hallmark of the nematic phase of Fe-based superconductors, including FeSe, but its origin is not yet understood. Here we report a high resolution Angle-Resolved Photoemission Spectroscopy study of single crystals of FeSe, accounting for the photon-energy dependence and making a detailed analysis of the temperature dependence. We find that the hole pocket undergoes a fourfold-symmetry-breaking distortion in the nematic phase below 90~K, but in contrast the changes to the electron pockets do not require fourfold symmetry-breaking. Instead, there is an additional separation of the existing $d_{xy}$ and $d_{xz/yz}$ bands - which themselves are not split within resolution. These observations lead us to propose a new scenario of "unidirectional nematic bond ordering" to describe the low-temperature electronic structure of FeSe, supported by a good agreement with 10-orbital tight binding model calculations. |
| spellingShingle | Watson, M Kim, T Rhodes, L Eschrig, M Hoesch, M Haghighirad, A Coldea, A Evidence for unidirectional nematic bond ordering in FeSe |
| title | Evidence for unidirectional nematic bond ordering in FeSe |
| title_full | Evidence for unidirectional nematic bond ordering in FeSe |
| title_fullStr | Evidence for unidirectional nematic bond ordering in FeSe |
| title_full_unstemmed | Evidence for unidirectional nematic bond ordering in FeSe |
| title_short | Evidence for unidirectional nematic bond ordering in FeSe |
| title_sort | evidence for unidirectional nematic bond ordering in fese |
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