title: Demonstration of photon-echo rephasing of spontaneous emission.
abstract: In this paper we report the first demonstration of "rephased amplified spontaneous emission" (RASE) with photon-counting detection. This protocol provides an all-in-one photon-pair source and quantum-memory that has applications as a quantum repeater node. The RASE protocol is temporally multimode, and in this demonstration the photon echo was generated in a way that is spatially multimode and includes intermediate storage between two potentially long-lived spin states. A correlation between spontaneous emission and its photon echo was observed, using an ensemble of Pr(3+) ions doped into a Y2SiO5 crystal. Alterations that would allow for the measurement of nonclassical correlations are identified. These should generally apply for future experiments in rare-earth ion crystals, which are promising systems for implementing highly-multiplexed quantum repeater operations.
authors.affiliation: Centre for Quantum Computation and Communication Technology, RSPE, Australian National University, Canberra, ACT 0200, Australia. Sarah.Beavan@anu.edu.au
authors.forename: Sarah E
authors.initials: SE
authors.lastname: Beavan
authors.forename: Morgan P
authors.initials: MP
authors.lastname: Hedges
authors.forename: Matthew J
authors.initials: MJ
authors.lastname: Sellars