Shape of photon-echo signals in a gas

Ko Okumura, Andrei Tokmakoff, Yoshitaka Tanimura

В. А. Зуйков, В. В. Самарцев, Ramil G. Usmanov

Igor V. Yevseyev, Valery M. Yermachenko, Самарцев Виталий Владимирович

As it was emphasized several times above, the phenomenon of the photon echo is an optical analog of the spin echo that has been discovered [ 1 ] about a decade earlier. That is why many ideas from the theory of the spin echo has been transferred to the theory of the photon echo and appeared to be fruitful there. One of these ideas put forward by Fernbach and Proctor [ 2 ] is the idea of the possibility of the use of the phenomenon of the spin echo for writing, storage, and processing of the data. The authors [ 2 ] determined the conditions under which the signals of the spin and stimulated spin echo can reproduce (direct or time-reversed) shape of one of the exciting pulses. The theoretical analysis was proved by the corresponding experiments.

Aleksey I. Alekseev, I. V. Evseev

Igor V. Yevseyev, Yu.V. Men'shikova, V. N. Tsikunov

A technique for the derivation of the electric field strength of varieties of photon-echo signals formed by exciting pulses with smooth envelopes is developed. This technique is based on joint solution of the d'Alembert and Schrödinger equations. The matrix of the evolution operator is constructed, which permits a description of the state of an individual atom (molecule) resulting from the action of an arbitrary exciting pulse sequence. The special form of exciting pulses with smooth envelope considered here is, together with the model of rectangular exciting pulses, one of the models that permits an analytical solution when the areas of the exciting pulses are not small. As an example, the technique is applied to the calculation of the electric field strength of signals of the modified three-level photon echo and the three-level photon echo formed by exciting pulses with smooth envelopes. The signal characteristics of photon-echo varieties formed by rectangular and non-rectangular exciting pulses are compared. It is shown that if the spectral lines of the resonant transitions are broad then the shapes and the peaks of the echo signals depend essentially on the shapes of the exciting pulses. The appearance of the fine structure of the modified three-level photon-echo and three-level photon-echo signal shapes is predicted. The necessity of setting up experiments aimed at observing the theoretically predicted special features of these photon-echo varieties is pointed out.

S. O. Elyutin, Sergey M. Zakharov, Edward A. Manykin