Field-Angle-Resolved Specific Heat in Na$_2$Co$_2$TeO$_6$: Evidence against Kitaev Quantum Spin Liquid
Fuente:
arXiv
Saved in:
| Main Authors: | , , , , , , |
|---|---|
| Format: | Preprint |
| Published: |
2024
|
| Subjects: | |
| Online Access: | |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| _version_ | 1866916653129793536 |
|---|---|
| author | Fang, Shengjie Imamura, Kumpei Mizukami, Yuta Namba, Ryuichi Ishihara, Kota Hashimoto, Kenichiro Shibauchi, Takasada |
| author_facet | Fang, Shengjie Imamura, Kumpei Mizukami, Yuta Namba, Ryuichi Ishihara, Kota Hashimoto, Kenichiro Shibauchi, Takasada |
| contents | Kitaev quantum spin liquids (KSLs) in layered honeycomb magnets are known to host Majorana quasiparticles, whose excitations depend strongly on the direction of the applied magnetic field. In the high-field phase of $α$-RuCl$_3$, specific heat measurements have revealed characteristic field-angle dependence of low-energy excitations consistent with the Kitaev model, providing bulk evidence for the KSL state. Here we present low-temperature measurements of specific heat $C(T)$ for another KSL candidate $\textrm{Na}_2\textrm{Co}_2\textrm{Te}\textrm{O}_6$ (NCTO) under field rotation within the honeycomb plane. Above the critical field of antiferromagnetic order, the field-angle dependence of $C/T$ exhibits minima along the bond directions, contrasting with the maxima observed in the KSL state of $α$-RuCl$_3$. Our analysis indicates nodeless, fully-gapped excitations, which are inconsistent with the angle-dependent Majorana excitations with gapless nodes predicted by the Kitaev model. These findings suggest that low-energy excitations in NCTO are governed by gapped magnon excitations rather than Majorana quasiparticles, providing thermodynamic evidence against a KSL state. |
| format | Preprint |
| id |
arxiv_https___arxiv_org_abs_2410_18449 |
| institution | arXiv |
| publishDate | 2024 |
| record_format | arxiv |
| spellingShingle | Field-Angle-Resolved Specific Heat in Na$_2$Co$_2$TeO$_6$: Evidence against Kitaev Quantum Spin Liquid Fang, Shengjie Imamura, Kumpei Mizukami, Yuta Namba, Ryuichi Ishihara, Kota Hashimoto, Kenichiro Shibauchi, Takasada Strongly Correlated Electrons Kitaev quantum spin liquids (KSLs) in layered honeycomb magnets are known to host Majorana quasiparticles, whose excitations depend strongly on the direction of the applied magnetic field. In the high-field phase of $α$-RuCl$_3$, specific heat measurements have revealed characteristic field-angle dependence of low-energy excitations consistent with the Kitaev model, providing bulk evidence for the KSL state. Here we present low-temperature measurements of specific heat $C(T)$ for another KSL candidate $\textrm{Na}_2\textrm{Co}_2\textrm{Te}\textrm{O}_6$ (NCTO) under field rotation within the honeycomb plane. Above the critical field of antiferromagnetic order, the field-angle dependence of $C/T$ exhibits minima along the bond directions, contrasting with the maxima observed in the KSL state of $α$-RuCl$_3$. Our analysis indicates nodeless, fully-gapped excitations, which are inconsistent with the angle-dependent Majorana excitations with gapless nodes predicted by the Kitaev model. These findings suggest that low-energy excitations in NCTO are governed by gapped magnon excitations rather than Majorana quasiparticles, providing thermodynamic evidence against a KSL state. |
| title | Field-Angle-Resolved Specific Heat in Na$_2$Co$_2$TeO$_6$: Evidence against Kitaev Quantum Spin Liquid |
| topic | Strongly Correlated Electrons |
| url | https://arxiv.org/abs/2410.18449 |