On Coherent Erasure of Long-Lived Photon Echo

An analysis of coherent suppression of long-lived photon echo is presented [9]. It is shown that upon multiple echo erasure and recovery the error probability increases owing to incomplete erasure. A method based on destructive interference is highly sensitive to fluctuations of the radiation parameters, particularly phase fluctuations. Requirements on the stability of the delay time in recording and erasing pairs of pulses are defined. A method to erase an echo by irradiating a medium with a resonance light is discussed, for the case in which the irradiation is longer than the optical decay. Relevant estimates are provided. It was ascertained that the latter method is not affected by fluctuations because in this case the medium asymptotically returns to the equilibrium distribution.