Photon echoes in optically dense media

Abstract

Coherent nonlinear multi-pulse processes, nonlinear waves and echo effects in resonant media are the topical problems of modern optics and important tools of coherent spectroscopy and quantum information science. We generalize the McCall-Hahn area theorem to the formation of an arbitrary photon echo generated during the multi-pulse excitation of the optically dense resonant media. The derived theorem made it possible to reveal the nonlinear mechanism of generation and evolution of the photon echo signals inside the media after a two-pulse excitation. We find that a series of selfreviving echo signals with total area of 2π or 0π is excited and propagates in the media depth, with each pulse having an individual area less than π. The resulting echo pulse train is a new alternative to the well-known soliton or breather. The developed pulse-area approach paves the way for more precise coherent spectroscopy, studies of different photon echo signals and quantum control of light pulses in the optically dense media.

Analysis of Imperfect Rephasing in Photon Echo-Based Quantum Memories

“…The spectral broadening of D is given by the light source, where the inhomogeneous broadening of the optical medium must be broader than that of D to satisfy the photon-echo scheme. A detailed photon-echo analysis in an optically dense medium was also studied [ 34 , 35 ].…”

Real-time ab initio description of the photon-echo mechanisms in extended systems: the case study of bulk GaAs

“…Spin-echo is usually achieved by means of the so called π-pulses. Here π (or fractions of π) refers to the pulse area [14,15], i.e. the time integral of the Rabi coupling Ω(t) = E(t) • μ. π-pulses lead to a global inversion of the microscopic dynamics due to strongly non linear effects, as can be understood in terms of the Rabi cycle in a two-levels system (TLS).…”