Mechanism of the insulator-to-metal transition and superconductivity in the spin liquid candidate NaYbSe2 under pressure
Abstract The quantum spin liquid candidate NaYbSe2 was recently reported to exhibit a Mott transition under pressure. Superconductivity was observed in the high-pressure metallic phase, raising the question concerning its relation with the low-pressure quantum spin liquid ground state. Here we combi...
| Main Authors: | , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Nature Portfolio
2022-02-01
|
| Series: | npj Quantum Materials |
| Online Access: | https://doi.org/10.1038/s41535-022-00429-7 |
| _version_ | 1818329684697415680 |
|---|---|
| author | Yuanji Xu Yutao Sheng Yi-feng Yang |
| author_facet | Yuanji Xu Yutao Sheng Yi-feng Yang |
| author_sort | Yuanji Xu |
| collection | DOAJ |
| description | Abstract The quantum spin liquid candidate NaYbSe2 was recently reported to exhibit a Mott transition under pressure. Superconductivity was observed in the high-pressure metallic phase, raising the question concerning its relation with the low-pressure quantum spin liquid ground state. Here we combine the density functional theory and the dynamical mean-field theory to explore the underlying mechanism of the insulator-to-metal transition and superconductivity and establish an overall picture of its electronic phases under pressure. Our results suggest that NaYbSe2 is a charge-transfer insulator at ambient pressure. Upon increasing pressure, however, the system first enters a semi-metallic state with incoherent Kondo scattering against coexisting localized Yb-4f moments, and then turns into a heavy-fermion metal. In between, there may exist a delocalization quantum critical point responsible for the observed non-Fermi liquid region with linear-in-T resistivity. The insulator-to-metal transition is therefore a two-stage process. Superconductivity emerges in the heavy-fermion phase with well-nested Yb-4f Fermi surfaces, suggesting that spin fluctuations may play a role in the Cooper pairing. NaYbSe2 might therefore be the 3rd Yb-based heavy-fermion superconductor with a very “high” T c than most heavy-fermion superconductors. |
| first_indexed | 2024-12-13T12:51:59Z |
| format | Article |
| id | doaj.art-50d6c271449245f8bfdbb07e195229a0 |
| institution | Directory Open Access Journal |
| issn | 2397-4648 |
| language | English |
| last_indexed | 2024-12-13T12:51:59Z |
| publishDate | 2022-02-01 |
| publisher | Nature Portfolio |
| record_format | Article |
| series | npj Quantum Materials |
| spelling | doaj.art-50d6c271449245f8bfdbb07e195229a02022-12-21T23:45:17ZengNature Portfolionpj Quantum Materials2397-46482022-02-01711710.1038/s41535-022-00429-7Mechanism of the insulator-to-metal transition and superconductivity in the spin liquid candidate NaYbSe2 under pressureYuanji Xu0Yutao Sheng1Yi-feng Yang2Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of SciencesBeijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of SciencesBeijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of SciencesAbstract The quantum spin liquid candidate NaYbSe2 was recently reported to exhibit a Mott transition under pressure. Superconductivity was observed in the high-pressure metallic phase, raising the question concerning its relation with the low-pressure quantum spin liquid ground state. Here we combine the density functional theory and the dynamical mean-field theory to explore the underlying mechanism of the insulator-to-metal transition and superconductivity and establish an overall picture of its electronic phases under pressure. Our results suggest that NaYbSe2 is a charge-transfer insulator at ambient pressure. Upon increasing pressure, however, the system first enters a semi-metallic state with incoherent Kondo scattering against coexisting localized Yb-4f moments, and then turns into a heavy-fermion metal. In between, there may exist a delocalization quantum critical point responsible for the observed non-Fermi liquid region with linear-in-T resistivity. The insulator-to-metal transition is therefore a two-stage process. Superconductivity emerges in the heavy-fermion phase with well-nested Yb-4f Fermi surfaces, suggesting that spin fluctuations may play a role in the Cooper pairing. NaYbSe2 might therefore be the 3rd Yb-based heavy-fermion superconductor with a very “high” T c than most heavy-fermion superconductors.https://doi.org/10.1038/s41535-022-00429-7 |
| spellingShingle | Yuanji Xu Yutao Sheng Yi-feng Yang Mechanism of the insulator-to-metal transition and superconductivity in the spin liquid candidate NaYbSe2 under pressure npj Quantum Materials |
| title | Mechanism of the insulator-to-metal transition and superconductivity in the spin liquid candidate NaYbSe2 under pressure |
| title_full | Mechanism of the insulator-to-metal transition and superconductivity in the spin liquid candidate NaYbSe2 under pressure |
| title_fullStr | Mechanism of the insulator-to-metal transition and superconductivity in the spin liquid candidate NaYbSe2 under pressure |
| title_full_unstemmed | Mechanism of the insulator-to-metal transition and superconductivity in the spin liquid candidate NaYbSe2 under pressure |
| title_short | Mechanism of the insulator-to-metal transition and superconductivity in the spin liquid candidate NaYbSe2 under pressure |
| title_sort | mechanism of the insulator to metal transition and superconductivity in the spin liquid candidate naybse2 under pressure |
| url | https://doi.org/10.1038/s41535-022-00429-7 |
| work_keys_str_mv | AT yuanjixu mechanismoftheinsulatortometaltransitionandsuperconductivityinthespinliquidcandidatenaybse2underpressure AT yutaosheng mechanismoftheinsulatortometaltransitionandsuperconductivityinthespinliquidcandidatenaybse2underpressure AT yifengyang mechanismoftheinsulatortometaltransitionandsuperconductivityinthespinliquidcandidatenaybse2underpressure |