Chiral superconductivity and chirality control

Chiral superconductors are a class of unconventional superconductors that break time-reversal symmetry and exhibit a handedness, i.e. chirality, in the phase of their superconducting order parameter—meaning the Cooper pairs have an angular momentum that creates a preferred rotational direction. This unique property can lead to exotic phenomena such as chiral edge states [1] and fractional vortices [2]. These chiral superconductors are of particular interest as they offer a platform for realizing Majorana quasiparticles [3] and provide insight into the interplay between topology, symmetry breaking, and superconductivity.

This project aims to characterize the chirality of potential chiral superconductors through electronic band structure by angle-resolved photoemission spectroscopy (ARPES) and related experimental techniques. Specifically, you will determine the symmetry of the superconducting gap [4], and look for signatures of chiral edge current in transport measurements. On the other hand, you will explore the capability of chirality control of chiral superconductors by ultrafast laser pulses, which has been demonstrated to induce and switch the chirality of a nonchiral crystal [5].

The selected candidate will work with Dr. Jianfeng Ge and Prof. Dr. Claudia Felser at MPI CPfS, specializing in electronic structures of chiral materials, as well as with Prof. Dr. Stefan Kaiser at TU Dresden, an expert in ultrafast control and spectroscopy of complex quantum materials. Ideal candidates will have a strong background in solid-state physics and knowledge across a range of experimental methodologies.