title: Evidence for nodeless superconductivity in NdO(1-x)F(x)BiS2 (x = 0.3 and 0.5) single crystals.
abstract: We study the superconducting pairing states of NdO(1-x)F(x)BiS2 (x = 0.3 and 0.5) by measuring the magnetic penetration depth Δλ(T) using the tunnel-diode-oscillator (TDO) technique. An upturn is observed in Δλ(T) as well as the magnetic susceptibility χ(T) in the low-temperature limit, which is attributed to the paramagnetism of Nd ions. After subtracting the paramagnetic contributions, the penetration depth Δλ(T) follows an exponential-type temperature dependence at T ≪ T(c), providing evidence of nodeless superconductivity for NdO(1-x)F(x)BiS2. This is further supported by the analyses of superfluid density ρ(s)(T), which can be well described by a BCS model with an energy gap of Δ(0) ∼ 2.15 k(B)T(c).
authors.affiliation: Center for Correlated Matter and Department of Physics, Zhejiang University, Hangzhou, Zhejiang 310058, People's Republic of China.
authors.forename: Lin
authors.initials: L
authors.lastname: Jiao
authors.forename: Zongfa
authors.initials: Z
authors.lastname: Weng
authors.forename: Jianzhong
authors.initials: J
authors.lastname: Liu
authors.forename: Jinglei
authors.initials: J
authors.lastname: Zhang
authors.forename: Guiming
authors.initials: G
authors.lastname: Pang
authors.forename: Chunyu
authors.initials: C
authors.lastname: Guo
authors.forename: Fei
authors.initials: F
authors.lastname: Gao
authors.forename: Xiyu
authors.initials: X
authors.lastname: Zhu
authors.forename: Hai-Hu
authors.initials: HH
authors.lastname: Wen
authors.forename: H Q
authors.initials: HQ
authors.lastname: Yuan