3D-2D crossover in the naturally layered superconductor (LaSe)1.14(NbSe2)

P. Samuely; P. Szabo; J. Kacmarcik; A. G. M. Jansen; A. Lafond; A. Meerschaut; A. Briggs

doi:10.1016/S0921-4534(01)01221-7

paper

3D-2D crossover in the naturally layered superconductor (LaSe)1.14(NbSe2)

arXiv:cond-mat/0111483 · doi:10.1016/S0921-4534(01)01221-7

Abstract

The temperature and angular dependencies of the resistive upper critical magnetic field $B_{c 2}$ reveal a dimensional crossover of the superconducting state in the highly anisotropic misfit-layer single crystal of (LaSe) $_{1.14}$ (NbSe $_{2}$ ) with the critical temperature $T_{c}$ of 1.23 K. The temperature dependence of the upper critical field $B_{c 2 ∥ ab} (T)$ for a field orientation along the conducting $(ab)$ -planes displays a characteristic upturn at 1.1 K and below this temperature the angular dependence of $B_{c 2}$ has a cusp around the parallel field orientation. Both these typical features are observed for the first time in a naturally crystalline layered system.

7 pages incl. 3 figures