A Universal Interacting Crossover Regime in Two-Dimensional Quantum Dots

TL;DR

This paper reveals a universal interacting crossover regime in two-dimensional quantum dots with strong spin-orbit coupling, where low-energy quasiparticles exhibit decay widths proportional to their energy, indicating a new quantum critical behavior.

Contribution

It introduces a new interacting quantum critical crossover energy scale in 2D quantum dots with spin-orbit coupling, expanding understanding of their low-energy physics.

Findings

Emergence of a new quantum critical crossover energy scale.

Low-energy quasiparticles have decay widths proportional to their energy.

Universal behavior across different symmetry classes.

Abstract

Interacting electrons in quantum dots with large Thouless number $g$ in the three classical random matrix symmetry classes are well-understood. When a specific type of spin-orbit coupling known to be dominant in two dimensional semiconductor quantum dots is introduced, we show that a new interacting quantum critical crossover energy scale emerges and low-energy quasiparticles generically have a decay width proportional to their energy. The low-energy physics of this system is an example of a universal interacting crossover regime.