Strong Superconducting Proximity Effect in Pb-Bi2Te3 Hybrid Structures

TL;DR

This paper reports a strong superconducting proximity effect in Pb-Bi2Te3 hybrid structures, enabling the creation of Josephson junctions and SQUIDs, which are promising platforms for exploring Majorana fermions in condensed matter systems.

Contribution

It demonstrates a robust proximity effect in Pb-Bi2Te3 structures, advancing the development of devices to investigate Majorana fermions.

Findings

Strong proximity effect observed in Pb-Bi2Te3 structures

Josephson junctions and SQUIDs successfully constructed

Potential platform for Majorana fermion research

Abstract

Majarona fermions (MFs) were predicted more than seven decades ago but are yet to be identified [1]. Recently, much attention has been paid to search for MFs in condensed matter systems [2-10]. One of the seaching schemes is to create MF at the interface between an s-wave superconductor (SC) and a 3D topological insulator (TI) [11-13]. Experimentally, progresses have been achieved in the observations of a proximity-effect-induced supercurrent [14-16], a perfect Andreev reflection [17] and a conductance peak at the Fermi level [18]. However, further characterizations are still needed to clarify the nature of the SC-TI interface. In this Letter, we report on a strong proximity effect in Pb-Bi2Te3 hybrid structures, based on which Josephson junctions and superconducting quantum interference devices (SQUIDs) can be constructed. Josephson devices of this type would provide a test-bed for exploring novel phenomena such as MFs in the future.