We consider semiconductor heterostructures in nanometric quantum wells,
whichas a consequence of the growth process display
at the rugged interfaces fractal characteristics, and largely influence optical and transport properties of the carriers
system. The photoluminescence and excited photoluminescence spectra in such
fractal conditions are theoretically analyzed, obtaining good agreement with
the experimental results. The Stokes shift and linewidth are strongly dependent
on the nonequilibrium thermomechanical-statistical state of the system. The
Stokes shift has its origin in the presence of a gain region in the absorption
spectrum, only present when the carriers system is in a statistical degenerate
state.
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