title: Superconductivity and disorder effect in TlNi2Se(2-x)S(x) compounds.
abstract: After our first discovery of multi-band superconductivity (SC) in the TlNi2Se2 crystal, we successfully grew a series of TlNi2Se(2-x)S(x) (0.0 ≤ x ≤ 2.0) single crystals. Measurements of resistivity, specific heat, and susceptibility were carried out on these crystals. Superconductivity with T(C) = 2.3 K was first observed in the TlNi2S2 crystal, which also appears to involve heavy electrons with an effective mass m* = 13-25 m(b), as inferred from the normal state electronic specific heat and the upper critical field, H(C2)(T). It was found that bulk SC and heavy-electron behavior is preserved in all the studied TlNi2Se(2-x)S(x) samples. In the mixed state, a novel change of the field dependence of the residual specific heat coefficient, γ(N)(H), occurs in TlNi2Se(2-x)S(x) with increasing S content. We also found that the T(C) value changes with the disorder degree induced by the partial substitution of S for Se, characterized by the residual resistivity ratio (RRR). Thus, the TlNi2Se(2-x)S(x) system provides a platform to study the effect of disorder on the multi-band SC.
authors.affiliation: Hangzhou Key Laboratory of Quantum Matter, Department of Physics, Hangzhou Normal University, Hangzhou 310036, People's Republic of China. Department of Physics, Zhejiang University, Hangzhou 310027, People's Republic of China.
authors.forename: Hangdong
authors.initials: H
authors.lastname: Wang
authors.forename: Qianhui
authors.initials: Q
authors.lastname: Mao
authors.forename: Huimin
authors.initials: H
authors.lastname: Chen
authors.forename: Qiping
authors.initials: Q
authors.lastname: Su
authors.forename: Chiheng
authors.initials: C
authors.lastname: Dong
authors.forename: Rajwali
authors.initials: R
authors.lastname: Khan
authors.forename: Jinhu
authors.initials: J
authors.lastname: Yang
authors.forename: Bin
authors.initials: B
authors.lastname: Chen
authors.forename: Minghu
authors.initials: M
authors.lastname: Fang