Driven anti-Bragg subradiant states in waveguide quantum electrodynamics

TL;DR

This paper theoretically investigates driven quantum dynamics in waveguide-coupled qubit arrays, revealing that strong driving induces long-lived subradiant states with enhanced quantum correlations beyond traditional subwavelength structures.

Contribution

It demonstrates that strong coherent driving creates new subradiant states in waveguide QED arrays with anti-Bragg periods, expanding the understanding of subradiance in nonlinear quantum regimes.

Findings

Strong driving induces subradiant eigenstates at anti-Bragg periods.

Long-lived quantum correlations are observed in driven subradiant states.

Subradiant states exist beyond conventional subwavelength array configurations.

Abstract

We study theoretically driven quantum dynamics in periodic arrays of two-level qubits coupled to the waveguide. We demonstrate, that strongly subradiant eigenstates of the master equation for the density matrix emerge under strong coherent driving for arrays with the anti-Bragg periods $d=\lambda/4,3\lambda/4$... This happens even though are no such states at low driving powers. Thus, our findings show that in the quantum nonlinear regime the domain of existence of subradiant states expands beyond conventional subwavelength structures. These driven states are directly manifested in long-living quantum correlations between the qubit excitations.