Theories of Superconducting Diode Effects

TL;DR

This paper reviews various theoretical mechanisms behind superconducting diode effects, highlighting the importance of symmetry breaking and exploring models in different materials and systems for potential applications.

Contribution

It provides a comprehensive overview of theoretical models for SDE, emphasizing the role of symmetry breaking and covering diverse material systems and mechanisms.

Findings

Ginzburg-Landau theory explains SDE with symmetry considerations

Microscopic models in noncentrosymmetric materials elucidate SDE origins

Various condensed matter systems can host superconducting diode effects

Abstract

Superconducting diode effects (SDE), both in bulk superconductors and in Josephson junctions, have garnered a lot of attention due to potential applications in classical and quantum computing, as well as superconducting sensors. Here we review various mechanisms that have been theoretically proposed for their realization. We first provide a brief historical overview and discuss the basic but subtle phenomenological Ginzburg-Landau theory of SDE, emphasizing the need to the simultaneous breaking of time-reversal and inversion symmetries. We then proceed to more microscopic treatments, focusing especially on implementations in noncentrosymmetric materials described by the Rashba-Zeeman model. Finally, we review proposals based on other condensed matter systems such as altermagnets, valley polarized and topological materials, and systems out of equilibrium.