A new superconductor derived from topological insulator heterostructure

Satoshi Sasaki; Kouji Segawa; Yoichi Ando

doi:10.1103/physrevb.90.220504

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arXiv · 1404.1707

A new superconductor derived from topological insulator heterostructure

Satoshi Sasaki·Kouji Segawa·Yoichi Ando

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Abstract

Topological superconductors (TSCs) are of significant current interest because they offer promising platforms for finding Majorana fermions. Here we report a new superconductor synthesized by intercalating Cu into a naturally-formed topological insulator (TI) heterostructure consisting of Bi2Se3 TI units separated by nontopological PbSe units. For the first time in a TI-based superconductor, the specific-heat behavior of this material suggests the occurrence of unconventional superconductivity with gap nodes. The existence of gap nodes in a strongly spin-orbit coupled superconductor would give rise to spin-split Andreev bound states that are the hallmark of topological superconductivity. Hence, this new superconductor emerges as an intriguing candidate TSC.

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Satoshi Sasaki, Kouji Segawa, Yoichi Ando. 2014-04-07. A new superconductor derived from topological insulator heterostructure. https://doi.org/10.1103/physrevb.90.220504

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