Bromine-doping dependence of crystal structure and superconductivity in FeSe1−xBrx

Effects of Mn doping on the normal-state transport of tetragonal FeSe superconductor up to 700 K

“…The refined lattice constants are a = 3.773(2) Å, 3.763(1) Å, 3.645(1) Å and 3.767(1) Å, c = 5.518(2) Å, 5.499(3) Å, 5.515(2) Å, 5.489(3) Å for x = 0.00, 0.02, 0.05 and 0.08, respectively. The lattice constants a and c of the undoped sample are in relatively good agreement with previous reports [12][13][14].…”

“…The minor impurity is identified as the hexagonal phase (α-phase). The diffraction peaks match with earlier reports of β-FeSe [12][13][14]. For the x = 0.08 sample, there exists an unidentified peak indicated with the asterisk, which presumably arises from high level of substituent ion.…”

“…Mizuguchi et al [8] have reported that the transition temperature of superconductivity rises to 27 K under the pressure of 1.48 GPa. Superconducting transition temperature can be also enhanced by chemical doping on the Fe site or Se site [9][10][11][12][13][14][15]. Superconducting FeSe undergoes a structural transition at low temperature.…”