Absence of vestigial order: how a nematic superconductor (not) behaves

by Pye Ton How (Institute of Physics, Academia Sinica)

Wednesday 19 Apr 2023, 15:00 → 16:00 Asia/Shanghai

ONLINE

Abstract

Multi-component superconductivity and superfluidity is a topic that has a long history and continues to be relevant even after decades.  A hallmark of such a system is that the superconducting phase spontaneously breaks more than the global U (1) symmetry, leading to rich, unconventional and exotic phenomenology. One of the interesting possibilities is the existence of a so-called vestigial ordered phase above the superconducting Tc, where the U (1) symmetry is restored, but not the other broken symmetry.  Oftentimes an unambiguous identification of multicomponent superconductivity is difficult, and its unique phenomenology serves as testable experimental signatures.  We will review the case of a two-component nematic superconductor, which breaks crystal rotational symmetry in addition to the global U (1) symmetry (MxBi2Se3 is a candidate material and the original motivation of our work).  We will discuss a number of experimental signatures that can prove the two-component nature of the order parameter, and how the vestigial nematic order is unlikely to be one of them, unfortunately [1].

1. Pye Ton How, Sung Kit Yip, PRB 107, 104514 (2023)

Biography

Dr. Pye Ton How is a postdoc at Academia Sinica, Taiwan. He graduated from the University of Cambridge in 2003 and got his PhD in 2011 at Cornell University. After PhD, he had a forced break in his career due to health issues, but he found the strength to return to science in 2016 as a postdoc at Academia Sinica. From 2019 until 2021, he worked with the National Center of Theoretical Sciences (NCTS) in Taiwan. His current attention is mainly on multicomponent superfluids and superconductors. His recent preprint [Pye Ton How, Sung Kit Yip, PRB 107, 104514 (2023)] goes in odd with popular theoretical paradigms and has attracted considerable attention from scientists working in the field of multicomponent superconductivity.

Division

Condensed Matter

Other information

Vedio link: https://vshare.sjtu.edu.cn/open/84f50b5880bc71c27d656aaa75309ae5