Interface superconductivity in La 1.48 Nd 0.4 Sr 0.12 CuO 4 /La 1.84 Sr 0.16 CuO 4 bilayers
Abstract
We identify a distinct superconducting phase at the interface of a La
1.48
Nd
0.4
Sr
0.12
CuO
4
(LNSCO)/La
1.84
Sr
0.16
CuO
4
(LSCO) epitaxial bilayer system using ac screening measurements. A model based on inter-diffusion of quasiparticles and condensate at the interface yields a thickness of
∼
25 nm for the interfacial layer. Two-dimensional superconductivity of the interface layer appears to be governed by Kosterlitz-Thouless-Berezinskii transition. A parallel magnetic field suppresses the superconducting transition temperature of this layer with a pair breaking parameter
α
varying as
H
2
.