PHOTON-ECHO IN A MEDIUM SUBJECTED SIMULTANEOUSLY TO EXTREMELY SHORT AND QUASI-RESONANT PULSES

An investigation is made of a two-pulse photon echo in a two-level med ium with strong inhomogeneous broadening, which is subjected simultane ously to extremely short and quasiresonant pulses. Two variants of the sequence of application of the two pulses are considered and it. is s hown that the kinetics of an echo signal depends largely an the sequen ce in which the pulses are applied. Suppression of the photon echo is predicted for both variants when a zero-area extremely short pulse is applied to a medium. A qualitative method for determination of the spa tial characteristics of such a combined echo is proposed and used. It is shown that, in the investigated cases, the angular distributions of the echo-signal intensity in an extended medium are noe as peaked as in the case of a conventional photon echo.