Retrieval of multiple spin waves from a weakly excited, metastable atomic ensemble

Abstract

The emission of light from a multiply excited atomic ensemble is examined and it is shown how symmetric (spin-wave) and non-symmetric states of excitation radiate into spatially separate field modes. This observation has potential application to single photon generation and spin wave entanglement, since in the presence of atomic interactions it can result in isolated single photon emission into a phase-matched field mode.

Cooperativity in light scattering by cold atoms

“…In this paper, we present an extended model based on a master equation in the single-excitation approximation. Such model provides a more complete description of the linear regime, useful to investigate the distinctions between classical and quantum features, even though a complete description of quantum correlations in our system requires to take into account a larger number of excitations [14,15]. In particular, we show that by a first-order perturbation expansion of the master equation we recover the previously adopted linear model from classical optics.…”

“…Finally, we notice that the exact master equation (2) can be written in terms of the effective Hamiltonian (15), using Eqs. (14), (15) and ρ = |Ψ Ψ|, as…”

Dephasing dynamics of Rydberg atom spin waves

“…Interactions then cause temporal dephasing of states with more than one excitation: an effect based on the variation of the interatomic potential in a spatially extended ensemble. The retrieval process maps the spin wave pair correlations onto the emitted light, via a phase matching condition [7], promising a fast, high-quality, singlephoton source. The efficiency of the source is limited by the probability amplitude of the single-excitation component of the many-body wavefunction.…”

“…In Ref. [7], we exhibit the direct relationship between states of spin wave excitation and those of photons emitted into a phase-matched mode of the field. As a consequence, the spin wave pair correlation function is equal to the Glauber's normalized second-order correlation function of the phase-matched field mode.…”

From Single Atoms to Engineered “Super-Atoms”: Interfacing Photons and Atoms in Free Space

“…The collective interaction of light with ensembles of absorbers and scatterers has been an active field of study since the early days of electromagnetism, while collective phenomena in spontaneous emission received wide attention with the pioneering work on Dicke superradiance from population inverted samples [103]. Early studies of collective emission from ensembles with few excitations [15,[104][105][106][107][108] (see also [109] and references therein) have been followed by a recent flourishing of analyses [17,18,43,[110][111][112][113][114][115][116][117]. Although this collective interaction is by itself an interesting question from the fundamental interest point of view, here we focus on the applied side, the controlled emission of a single photon and its reabsorption by small atomic samples.…”