Coherent backscattering of light from ultracold and optically dense atomic ensembles

Abstract

We review experimental and theoretical studies of coherent backscattering of near resonant radiation from an ultracold atomic gas in the weak localization regime. Recent accomplishments in high resolution spectroscopy of atomic ensembles based on the coherent backscattering process are discussed. We also propose several new experimental schemes for time-dependent spectroscopy as applied to multiple scattering in the regime of weak localization.A coherent backscattering image of light scattered from an atomic cloud of 85 Rb atoms in the lin ⊥ lin polarization channel

Spectrum of coherently backscattered light from two atoms

“…Finally, the correlation functions relevant for the evaluation of the total ladder and crossed contributions [see Eqs. (11), (12) where Q [1] ss = G 0 VG 0 j. Numerical results for the elastic and inelastic intensities for different detunings can be found in the main text.…”

“…(5) describes the evolution of one-point correlation functions, whereas G (1) ss (τ ) is a two-point correlation function. By virtue of the quantum regression theorem [24], the latter also satisfies Eq.…”

“…Multiple scattering of light in cold atomic gases has become an area of intense theoretical and experimental research (for a recent review, see [1]). On the experimental side, the successful observation of coherent backscattering (CBS) of light in clouds of cold atoms [2,3] demonstrated the potential of finely tunable atomic media for detailed studies of localization and transport phenomena [4] in the weak and, prospectively, strong localization regime.…”

“…where G 0 (z) = (z1 1 255 − A) −1 , and the superscripts [0], [1], and [2] indicate terms on the order g 0 , g 1 , and g 2 , respectively. Expression (B7) can be simplified since (B6) gives a spectrum in the h h channel.…”

Angular distribution of single-photon superradiance in a dilute and cold atomic ensemble

“…The enhancement factor for the helicity preserving channel is close to two which is typical for a 0-1 transition. For another channel it is much less because of the single scattering contribution to the background [39,40].…”