Shot noise in semiclassical chaotic cavities

TL;DR

This paper develops a semiclassical theory for shot noise in chaotic cavities, reproducing universal results and analyzing how shot noise suppression depends on Ehrenfest time, while ensuring unitarity of the scattering matrix.

Contribution

It introduces a trajectory-based semiclassical framework for shot noise that accounts for finite Ehrenfest time effects and maintains unitarity, extending previous approaches.

Findings

Reproduces random matrix theory results in the universal regime

Shows exponential suppression of Fano factor with increasing Ehrenfest time

Ensures unitarity of the scattering matrix in semiclassical regime

Abstract

We construct a trajectory-based semiclassical theory of shot noise in clean chaotic cavities. In the universal regime of vanishing Ehrenfest time $\tE$, we reproduce the random matrix theory result, and show that the Fano factor is exponentially suppressed as $\tE$ increases. We demonstrate how our theory preserves the unitarity of the scattering matrix even in the regime of finite $\tE$. We discuss the range of validity of our semiclassical approach and point out subtleties relevant to the recent semiclassical treatment of shot noise in the universal regime by Braun et al. [cond-mat/0511292].