Superconducting Symmetry Studied from Impurity Effects in Single-Crystal Fe1-yMySe0.3Te0.7 (M = Co, Ni, Zn)

作者：Inabe Takuya^*; Kawamata Takayuki; Noji Takashi; Adachi Tadashi; Koike Yoji

来源：Journal of the Physical Society of Japan, 2013, 82(4): 044712.

DOI：10.7566/JPSJ.82.044712

• Fe-based superconductor
• impurity effect
• superconducting symmetry
• superconducting transition temperature
• residual resistivity

We have investigated the suppression of the superconducting transition temperature, T-c, with an increase of the residual resistivity, rho(0), through the substitution of M (M = Co, Ni, Zn) for Fe in Fe1-yMySe0.3Te0.7 single crystals, in order to clarify the symmetry of the superconducting gap in FeSe1-xTex. Small, large and very small suppression of T-c have been observed through the Co, Ni, and Zn substitution, respectively. The magnitude of the suppression rate is hardly explained in terms of the pair-breaking effect due to potential scattering calculated based on the Abrikosov-Gor'kov theory, even if errors in the estimation of the carrier concentration, effective mass and rho(0) were taken into account. Accordingly, these results suggest that the superconducting symmetry is the s(++)-wave in FeSe1-xTex.

• 出版日期2013-4