Photoselection of impurity molecules in amorphous media over the zero-phonon linewidth

The shape of a multiwell hole, which is produced upon burning a number of closely spaced equidistant spectral holes in the low-temperature absorption spectrum of an impurity amorphous solid, is studied. When the bottom of such a hole is probed by the wavelength-modulated light, the transmission and luminescence of the sample become modulated. This modulation is caused by a subsystem of impurity molecules, which differs from a total ensemble by a smaller scatter in the zero-phonon linewidth and a smaller (by a factor of 2-3) mean value of this width. The study of the photophysical parameters of this subsystem can yield useful information for simulating the nanostructure of an amorphous body. (C) 2001 MAIK "Nauka/Interperiodica".