Generation of transient inversion gratings with an ultrashort period in media exhibiting a phase memory under multipulse interaction conditions

Multipulse excitation of a resonant medium by a laser field is considered. It is shown that one stable long-lived grating with an ultrashort period, i.e., a period much shorter than the wavelength of the exciting laser radiation, can form in such a medium. A study is reported of the interaction of light with gratings of this type and of generation of transient signals by these gratings.