Storage and retrieval of a light in telecomband in a cold atomic ensemble

TL;DR

This paper demonstrates the first experimental storage and retrieval of telecom-band light in a cold atomic ensemble, simplifying quantum memory interfaces for long-distance quantum communication.

Contribution

It provides the first proof-of-principle experiment of directly storing telecom-band photons in a cold atomic ensemble without frequency conversion.

Findings

Successful storage and retrieval of telecom photons

Use of nonlinear processes in a cold atomic ensemble

Potential for improved quantum communication links

Abstract

A telecom photon is a suitable information carrier in a fiber-based quantum network due to its lower transmission loss in fiber. Because of the paucity of suitable atomic system, usually the photon connecting different memories is in near infrared band, therefore the frequency conversion of the photon in and out of telecomband has to be required to realize the interface between the atomic-based memory and the photon-based carrier. In order for that, two atomic or other systems which could realize the frequency conversion have to be taken into account, and besides, one more atomic system as a storing media is need. So the ability of storing a photon in telecomband is an interesting and exciting topic. In this work, we give a first experimental proof of principle of storing a light in telecomband. The telecom light is directly stored and retrieved later through two nonlinear processes via an inverted-Y configuration in a cold atomic ensemble, therefore the interface between the memory and photon in other proposals is not needed. We believe our work may open a new avenue for long-distance quantum communication.