Subluminal light pulse propagation in a {\Lambda}-type atom-molecule coupled system

TL;DR

This paper theoretically demonstrates electromagnetically induced transparency (EIT) in a {b1}-type atom-molecule system, enabling slow light propagation with significant delay and high transmission in ultracold molecular media.

Contribution

It introduces a novel EIT-like phenomenon in atom-molecule systems and shows how to achieve ultra-slow light with high transmission using a control field.

Findings

Achieves a 1 ms delay for light over 1 cm in ultracold molecules.

Reduces group velocity of light below 100 m/s.

Maintains over 25% transmission during slow light propagation.

Abstract

We show theoretically the presence of electromagnetically induced transparency (EIT) like feature in a {\Lambda}-type atom-molecule coupled system. We demonstrate that EIT in such a systems has a sharp dispersion characteristic which is useful to slow down light propagation in a medium. The results of our model calculations show that, it is possible to achieve a time delay of the order of 1 ms for a probe field propagating a distance of 1 cm through a medium of ultracold diatomic molecules coupled to the continuum of atom-atom collisional states with a control field. This enables one to reduce the group velocity of the light much below 100 m/s with more than 25% transmission.