Unusual normal and superconducting state properties observed in hydrothermal Fe1-xSe flakes

Authors:
  • SLShaobo Liu
    Shaobo Liu
  • SMSheng Ma
    Sheng Ma
  • ZWZhaosheng Wang
    Zhaosheng Wang
  • WHWei Hu
    Wei Hu
  • ZLZian Li
    Zian Li
  • QLQimei Liang
    Qimei Liang
  • HWHong Wang
    Hong Wang
  • YZYuhang Zhang
    Yuhang Zhang
  • ZLZouyouwei Lu
    Zouyouwei Lu
  • JYJie Yuan
    Jie Yuan
  • KJKui Jin
    Kui Jin
  • JLJian-Qi Li
    Jian-Qi Li
Preprint
Publisher website
Google Scholar
Abstract
The electronic and superconducting properties of Fe1-xSe single-crystal flakes grown hydrothermally are studied by the transport measurements under zero and high magnetic fields up to 38.5 T. The results contrast sharply with those previously reported for nematically ordered FeSe by chemical-vapor-transport (CVT) growth. No signature of the electronic nematicity, but an evident metal-to-nonmetal crossover with increasing temperature, is detected in the normal state of the present hydrothermal samples. Interestingly, a higher superconducting critical temperature Tc of 13.2 K is observed compared to a suppressed Tc of 9 K in the presence of the nematicity in the CVT FeSe. Moreover, the upper critical field in the zero-temperature limit is found to be isotropic with respect to the field direction and to reach a higher value of ~42 T, which breaks the Pauli limit by a factor of 1.8.
All Related Versions