Transport, shot noise, and topology in AC-driven dimer arrays

TL;DR

This paper investigates how AC-driven dimer chains exhibit topological features in transport and shot noise, enabling topological phase identification through noise measurements and analyzing coherence requirements for experiments.

Contribution

It introduces a method to detect topological phases via shot noise in AC-driven dimer arrays and develops an efficient computational approach for zero-frequency noise.

Findings

Transport shows topological signatures in current suppression and Fano factor.

Shot noise measurements can map the topological phase diagram.

Edge states and effective Hamiltonian explain observed phenomena.

Abstract

We analyze an AC-driven dimer chain connected to a strongly biased electron source and drain. It turns out that the resulting transport exhibits fingerprints of topology. They are particularly visible in the driving-induced current suppression and the Fano factor. Thus, shot noise measurements provide a topological phase diagram as a function of the driving parameters. The observed phenomena can be explained physically by a mapping to an effective time-independent Hamiltonian and the emergence of edge states. Moreover, by considering quantum dissipation, we determine the requirements for the coherence properties in a possible experimental realization. For the computation of the zero-frequency noise, we develop an efficient method based on matrix-continued fractions.