Doubly-heralded single-photon absorption by a single atom

TL;DR

This paper demonstrates a highly controlled quantum interface where a single photon generated via SPDC is absorbed by a single trapped ion, with dual heralding to confirm the absorption event, advancing quantum communication capabilities.

Contribution

It introduces a novel doubly-heralded detection scheme that significantly suppresses background noise, enabling reliable photon-to-atom quantum state transfer.

Findings

Successful demonstration of doubly-heralded single-photon absorption by a single atom.

Enhanced signal-to-noise ratio in photon detection through a new background suppression method.

Potential for improved quantum communication protocols using this interface.

Abstract

We report on a single-photon-to-single-atom interface, where a single photon generated by Spontaneous Parametric Down Conversion (SPDC) is absorbed by a single trapped ion. The photon is heralded by its time-correlated partner generated in the SPDC process, while the absorption event is heralded by a single photon emitted in its course. Coincidence detection marks doubly-heralded absorption, enabling photon-to-atom quantum state transfer [1, 2]. Background in the coincidence measurement is strongly suppressed by a new method that discriminates real absorption events from dark count-induced coincidences.