Cavity dark mode mediated by atom array without atomic scattering loss

TL;DR

This paper demonstrates a ring cavity strongly coupled with an atom array, creating a cavity dark mode that reduces atomic scattering loss and allows for efficient optical mode conversion and phase control, advancing quantum optical engineering.

Contribution

It introduces a novel cavity dark mode mediated by an atom array with configurable structure, enabling lossless strong coupling and phase manipulation without atomic scattering.

Findings

Observation of a cavity dark mode locked to atom positions

Decoupling of dark mode from atomic scattering loss

Ability to impart large phase shifts via atom array translation

Abstract

We realize a ring cavity strongly interacting with an atom array with configurable spatial structures. By preparing the atom array with a maximized structure factor, we observe the emergence of a cavity dark mode, where the standing-wave nodes are dynamically locked to the positions of the atoms. The dark mode is decoupled from the atoms, protecting the system from dissipation through atomic scattering, but still mediates strong coupling and enables efficient conversion between two optical modes. Moreover, we impart an arbitrary large phase shift on the converted optical fields by translating the atom array. This strongly interacting ring cavity system with single-atom addressability opens ways to quantum optical engineering and the generation of photonic quantum states based on the geometrical structure of atom arrays.