Subradiant collective states for precision sensing via transmission spectra

TL;DR

This paper explores the use of subradiant states in quantum emitter ensembles to enhance precision sensing by analyzing their transmission spectra, leading to improved detection of external perturbations.

Contribution

It introduces a method to utilize subradiant collective states in atomic arrays and waveguides for quantum metrology, demonstrating their potential for high-sensitivity measurements.

Findings

Subradiant states produce sharp, narrow features in transmittance spectra.

Enhanced sensitivity to external perturbations like electromagnetic fields and gravitational gradients.

Applications include atomic clocks and spatially resolved emitter imaging.

Abstract

When an ensemble of quantum emitters interacts with a common radiation field, their emission becomes collective, giving rise to superradiant and subradiant states, characterized by broadened and narrowed linewidths. In this work, we propose to harness subradiant states for quantum metrology; such states naturally arise in subwavelength-spaced atomic arrays in free space and in small ensembles of emitters coupled to one-dimensional waveguides. We demonstrate that their collective optical response yields sharp, narrow features in the transmittance spectrum, which can be used to enhance sensitivity to external perturbations. This improved sensitivity can be applied to atomic clock operation, spatially resolved imaging of emitter positions, and enables precise detection of both global and spatially varying detunings (such as those induced by electromagnetic fields or gravitational gradients).