Theoretical study of large proximity-induceds-wave-like pairing from ad-wave superconductor

Abstract

Proximity effect is used to generate effective topological superconductor by\nplacing strong spin orbit interacting metals with superconducting materials,\naiming to produce Majorana zero modes useful for topologically protected\nquantum computations. In recent experiments high $T_c$ material\n$\\text{Bi}_2\\text{Sr}_2\\text{CaCu}_2\\text{O}_{8+\\delta}$ is put in contact with\na few quintuple layer thick $\\text{Bi}_2\\text{Se}_3$, and conflicting\nexperimental results are reported. We use standard mean field approach to study\nthis heterostructure, and find it is unlikely to have large proximity induced\nsuperconducting gap. The claimed observed s-wave gap might not be purely\nsuperconducting coherence gap despite its seemingly correct temperature\ndependence. Further study on the proximity induced bulk coherence gap and the\nband structure at the interface should shed light on this issue.\n