Photon echo quantum memory with complete use of natural inhomogeneous broadening

TL;DR

This paper introduces a novel rephasing mechanism for photon echo quantum memory that fully utilizes natural inhomogeneous broadening, significantly enhancing efficiency and practical applicability.

Contribution

A new active rephasing method that achieves perfect retrieval regardless of initial broadening, maximizing the use of resonant atoms for improved quantum memory performance.

Findings

Achieves perfect retrieval of stored light in photon echo memory.

Maximizes optical depth by exploiting all resonant atoms.

Enables versatile implementations of photon echo quantum memory.

Abstract

The photon echo quantum memory is based on a controlled rephasing of the atomic coherence excited by signal light field in the inhomogeneously broadened resonant line. Here, we propose a novel active mechanism of the atomic rephasing which provides a perfect retrieval of the stored light field in the photon echo quantum memory for arbitrary initial inhomogeneous broadening of the resonant line. It is shown that the rephasing mechanism can exploit all resonant atoms which maximally increases an optical depth of the resonant transition that is one of the critical parameters for realization of highly efficient quantum memory. We also demonstrate that the rephasing mechanism can be used for various realizations of the photon echo quantum memory that opens a wide road for its practical realization.