Tunable ultrahigh reflection with broadband via collective atom-atom interaction in waveguide-QED system

TL;DR

This paper introduces a method to achieve and control broadband ultrahigh reflection in waveguide-QED systems through collective atom interactions, with potential applications in quantum and optical devices.

Contribution

The study demonstrates a tunable broadband reflection scheme in waveguide-QED systems using collective atom interactions and frequency modulation strategies.

Findings

Achieved broadband complete reflection via collective atom interactions.

Enhanced reflection windows by increasing atom number and applying frequency gradients.

Dynamic control of reflection bandwidth and center frequency with external fields.

Abstract

We present a scheme for achieving broadband complete reflection by constructing photonic bandgap via collective atom-atom interaction in a one-dimensional (1D) waveguide quantum electrodynamics (QED) system. Moreover, we propose several strategies to further expand the ultrahigh reflection windows, including increasing the number of atoms with separations near the Bragg distance and inducing gradient frequency modulation among the atoms. The center frequency and bandwidth of the ultrahigh reflection window are dynamically adjustable by applying external electromagnetic field. The results here can enrich the many-body physics of waveguide-QED system and offer a pathway for achieving broadened ultrahigh reflection in a controllable way, which can find important applications in the realms of chip-integrated band filter, quantum storage, optical switching, and wavelength-selective devices.