Resonant Dipole-Dipole Interactions in Electromagnetically Induced Transparency

TL;DR

This paper theoretically explores how resonant dipole-dipole interactions influence electromagnetically induced transparency, revealing effects on linewidth, frequency shifts, and implications for quantum memory efficiency.

Contribution

It provides a detailed theoretical analysis of RDDI effects on EIT, highlighting the role of collective interactions and their impact on transparency and storage.

Findings

RDDI causes linewidth broadening and frequency shifts in EIT.

EIT transparency narrows with increased cooperative linewidth.

Implications for reduced efficiency in EIT-based quantum memory.

Abstract

Resonant dipole-dipole interaction (RDDI) is ubiquitous in light-matter interacting systems and is responsible for many fascinating properties of collective radiations. Here we theoretically investigate the role of RDDI in electromagnetically induced transparency (EIT). The resonant dipole-dipole interactions manifest in the cooperative spontaneous emission of the probe light transition, which give rise a broadened linewidth and associated collective frequency shift. This cooperative linewidth originates from the nonlocal and long-range RDDI, which can be determined by the atomic density, optical depth, and macroscopic length scales of the atomic ensemble. We present that EIT spectroscopy essentially demonstrates all-order multiple scattering of RDDI. Furthermore, we find that EIT transparency window becomes narrower as the cooperative linewidth increases, which essentially reduces the storage efficiency of slow light as EIT-based quantum memory application.