The layered bismuth oxy-sulfide materials, which are structurally related to the Fe-pnictides/chalcogenides and cuprates superconductors, have brought substantial attention for understanding the physics of reduced dimensional superconductors. We have examined the pairing symmetry of recently discovered BiCh2-based superconductor, La1−xCexOBiSSe with x = 0.3, through transverse field (TF) muon spin rotation measurement, in addition we present the results of magnetization, resistivity and zero field (ZF) muon spin relaxation measurements. Bulk superconductivity has been observed below 2.7 K for x = 0.3, verified by resistivity and magnetization data. The temperature dependence of the magnetic penetration depth has been determined from TF-μSR data can be described by an isotropic two-gap s+s wave model compared to a single gap s- or anisotropic s-wave models, the resemblance with Fe-pnictides/chalcogenides and MgB2. Furthermore, from the TF-μSR data, we have determined the London's penetration depth λL(0) = 452(3) nm, superconducting carrier's density ns = 2.18(1) ×1026 carriers/m3 and effective mass enhancement m∗ = 1.66(1) me, respectively. No signature of spontaneous internal field is found down to 100 mK in ZF-μSR measurement suggest that time-reversal symmetry is preserved in this system.
@article{arxiv.2007.03752,
title = {Multigap superconductivity in the new BiCh$_{2}$-based layered superconductor La$_\mathrm{0.7}$Ce$_\mathrm{0.3}$OBiSSe},
author = {A. Bhattacharyya and D. T. Adroja and R. Sogabe and Y. Goto and Y. Mizuguchi and A. D. Hillier},
journal= {arXiv preprint arXiv:2007.03752},
year = {2020}
}