Transport phenomena in the asymmetric quantum multibaker map

TL;DR

This paper demonstrates the existence of a finite quantum current in a modified quantum multibaker map, revealing a purely quantum ratchet mechanism that breaks classical symmetry constraints and advances understanding of directed transport in chaotic quantum systems.

Contribution

It introduces a modified quantum multibaker map that exhibits a finite quantum current without classical analogues, providing a new approach to quantum ratchets and transport phenomena.

Findings

Finite asymptotic quantum current observed

Quantum ratchet mechanism identified

Multibaker map as a model for quantum chaos transport

Abstract

By studying a modified (unbiased) quantum multibaker map, we were able to obtain a {\em finite} asymptotic quantum current without a classical analogue. This result suggests a general method for the design of {\em purely} quantum ratchets, and sheds light on the investigation of the mechanisms leading to net transport generation by breaking symmetries of quantum systems. Moreover, we propose the multibaker map as a resource to study directed transport phenomena in chaotic systems without bias. In fact, this is a paradigmatic model in classical and quantum chaos, but also in statistical mechanics.