Controllable unidirectional transport and photon storage in an one-dimensional lattice with complex hopping rates

TL;DR

This paper demonstrates how a non-Hermitian one-dimensional lattice with complex hopping rates can enable robust, controllable unidirectional photon transport and storage, with immunity to defects and backscattering, using synthetic magnetic fluxes.

Contribution

It introduces a novel non-Hermitian lattice design with synthetic magnetic fluxes for unidirectional transport and photon storage, advancing optical control techniques.

Findings

Achieved robust unidirectional transport immune to defects.

Proposed a controllable photon storage and reversal structure.

Enhanced storage efficiency with gain compensation.

Abstract

We study an one-dimensional non-Hermitian lattice with complex hopping rates, which can be realized by a quasi-one-dimensional sawtooth-type Hermitian lattice after adiabatic elimination with proper conditions. By means of synthetic magnetic fluxes, the imaginary parts of the complex hopping rates can be modulated by additional phase, thus a non-reciprocal structure arises. With this lattice, one can realize robust unidirectional transport for both single-site and Gaussian excitations, which is immune to defects and backscattering. Furthermore, we proposed a sandwich structure based on the non-Hermitian lattice, which can be used for realizing controllable photon storage and reversal. The storage time and range can be artificially controlled within limits, and the storage efficiency can be increased via a finite gain compensation. The proposal of controllable photon transport in this paper opens up a new path for unidirectional photon transport and provides a promising platform for optical control and manipulation.