PHOTOPHYSICAL ABLATION OF POROUS SILICON AS MANIFESTATION OF MESOSCOPIC FORCE FLUCTUATIONS IN NANOWIRES V.P. Aksenov, G.N. Mikhailova A. Prokhorov General Physical Institute, Vavilov St., 38, 119991, Moscow, Russia Laser ablation of porous silicon is considered from the point of view of photophysical mechanism and the ablation of quantum nanowires of silicon. Laser ablation of porous silicon as a function of laser wavelength and width of silicon nanowires was studied in our experiments. The time-resolved evolution of the cloud of silicon particles produced by laser ablation has been determined in-situ from the analysis of the photoluminescence kinetics. Experimental results were explained on the base of photophysical mechanism of ablation suggested by B. Lukynchuk et al. and phenomenological model of nanostructure destroying. According to the models fotoexcited carriers in quantum wires of porous silicon destroy it in consequence of space limited motion in quantum wires. The squeezed electron-hole plasma heated by IR-laser radiation may produce a damage of silicon nanowires.