Optical Cooling of Dye-Doped Polymer Films during Photon Echo Emission

Some spectral features of the femtosecond self-diffraction, primary and stimulated photon echo signals on the $S_1\to S_0$ (at the wavelength 795 nm) of the phthalocyanine molecules HW 1009 type in the polyvinylbutyral film at room temperatures were observed. It is shown that under resonant pulsed excitation of various sections of the optical absorption band the spectral shifts for responses could be Stokes and anti-Stokes as well: at pump wavelength $\lambda=765$ nm there is Stokes shift and at $\lambda=790$ nm there is anti-Stokes shift. A simple femtosecond coherent laser cooling regime for dye-doped polymer film is proposed.