Ultralong Photon Echo Storage Using Optical Locking

TL;DR

This paper demonstrates ultralong photon echo storage exceeding 50% efficiency by using optical locking with control pulses to extend coherence time, promising for quantum communication.

Contribution

It introduces a method of optical locking in three-pulse photon echoes to significantly extend storage time beyond traditional limits.

Findings

Achieved over 50% photon echo retrieval efficiency.

Extended photon echo decay time beyond spin homogeneous decay.

Potential application in long-distance quantum communication.

Abstract

An ultralong photon storage with more than 50% retrieval efficiency is presented in the three-pulse photon echoes by using a pair of control pulses, where the control pulses play to freeze atoms dephasing process conditionally by transferring excited atoms to an auxiliary state and returning them back later. The observed photon echo decay time much longer than the spin homogeneous decay time is potential for long distance quantum communications.