High- Superconductivity in FeSe at High Pressure: Dominant Hole Carriers and Enhanced Spin Fluctuations
- Chinese Academy of Sciences (CAS), Beijing (China)
- Chinese Academy of Sciences (CAS), Beijing (China); Yunnan Univ., Kunming (China)
- Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
- Univ. of Tokyo (Japan)
- Nagoya Univ. (Japan)
- Tsinghua Univ., Beijing (China)
- Yunnan Univ., Kunming (China)
- Univ. of Missouri, Columbia, MO (United States)
The importance of electron-hole interband interactions is widely acknowledged for iron-pnictide superconductors with high transition temperatures (Tc). However, high-Tc superconductivity without hole carriers has been suggested in FeSe single-layer films and intercalated iron-selenides, raising a fundamental question whether iron pnictides and chalcogenides have different pairing mechanisms. Here, we study the properties of electronic structure in another high-Tc phase induced by pressure in bulk FeSe from magneto-transport measurements and first-principles calculations. With increasing pressure, the low-Tc superconducting phase transforms into high-Tc phase, where we find the normal-state Hall resistivity changes sign from negative to positive, demonstrating dominant hole carriers in striking contrast to other FeSe-derived high-Tc systems. Moreover, the Hall coefficient is remarkably enlarged and the magnetoresistance exhibits anomalous scaling behaviours, evidencing strongly enhanced interband spin fluctuations in the high-Tc phase. These results in FeSe highlight similarities with high-Tc phases of iron pnictides, constituting a step toward a unified understanding of iron-based superconductivity.
- Research Organization:
- Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)
- Sponsoring Organization:
- USDOE Office of Science (SC), Basic Energy Sciences (BES); USDOE
- Grant/Contract Number:
- AC05-00OR22725
- OSTI ID:
- 1376522
- Alternate ID(s):
- OSTI ID: 1350795
- Journal Information:
- Physical Review Letters, Vol. 118, Issue 14; ISSN 0031-9007
- Publisher:
- American Physical Society (APS)Copyright Statement
- Country of Publication:
- United States
- Language:
- English
Similar Records
NMR investigation of the Fe Se high- superconductor ( K)
Long-range magnetic order in hydroxide-layer-doped