Dynamical signatures of molecular symmetries in nonequilibrium quantum transport

TL;DR

This paper introduces a method to detect molecular symmetries in quantum transport systems by analyzing quantum current signatures resulting from specific initial conditions and local noise probes, revealing symmetry-related dynamics.

Contribution

It presents a novel approach to identify symmetries through current measurements, utilizing anti-symmetric initial states and local noise probes to detect unique dynamical signatures.

Findings

Detection signatures include quasi-stationary plateaus and multi-exponential decays.

Method is demonstrated on a 4-site model and para-benzene ring.

Signatures are robust under weak disorder.

Abstract

Symmetries play a crucial role in ubiquitous systems found in Nature. In this work, we propose an elegant approach to detect symmetries by measuring quantum currents. Our detection scheme relies on initiating the system in an anti-symmetric initial condition, with respect to the symmetric sites, and using a probe that acts like a local noise. Depending on the position of the probe the currents exhibit unique signatures such as a quasi-stationary plateau indicating the presence of meta-stability and multi-exponential decays in case of multiple symmetries. The signatures are sensitive to the probe and vanish completely when the timescale of the coherent system dynamics is much longer than the timescale of the probe. These results are demonstrated using a $4$-site model and an archetypal example of the para-benzene ring and are shown to be robust under a weak disorder.