Quantum Chaos in Open versus Closed Quantum Dots: Signatures of Interacting Particles

TL;DR

This paper compares quantum chaos signatures in open and closed quantum dots, highlighting how electron interactions and quantum interference influence conductance fluctuations and dephasing in mesoscopic systems.

Contribution

It provides a comprehensive review of mesoscopic fluctuations in quantum dots, emphasizing differences between open and tunneling regimes and applying theoretical models to interpret experimental data.

Findings

Universal conductance fluctuation statistics in open and closed dots

Electron interactions significantly affect tunneling conductance

Dephasing rates can be extracted from open dot measurements

Abstract

This paper reviews recent studies of mesoscopic fluctuations in transport through ballistic quantum dots, emphasizing differences between conduction through open dots and tunneling through nearly isolated dots. Both the open dots and the tunnel-contacted dots show random, repeatable conductance fluctuations with universal statistical proper-ties that are accurately characterized by a variety of theoretical models including random matrix theory, semiclassical methods and nonlinear sigma model calculations. We apply these results in open dots to extract the dephasing rate of electrons within the dot. In the tunneling regime, electron interaction dominates transport since the tunneling of a single electron onto a small dot may be sufficiently energetically costly (due to the small capacitance) that conduction is suppressed altogether. How interactions combine with quantum interference are best seen in this regime.