| Abstract: | We investigate the dynamic susceptibility and one-dimensional density of states in an initially sinusoidal superlattice containing
simultaneously 2D phase inhomogeneities simulating correlated rough-nesses of superlattice interfaces and 3D amplitude inhomogeneities
of the superlattice layer materials. The analytic expression for the averaged Green’s function of the sinusoidal superlattice
with two phase inhomogeneities is derived in the Bourret approximation. It is shown that the effect of increasing asymmetry
in the peak heights of dynamic susceptibility at the Brillouin zone boundary of the superlattice, which was discovered earlier
15] upon an increase in root-mean-square (rms) fluctuations, also takes place upon an increase in the correlation wavenumber
of inhomogeneities. However, the peaks in this case also become closer, and the width and depth of the gap in the density
of states decrease thereby. It is shown that the enhancement of rms fluctuations of 3D amplitude inhomogeneities in a superlattice
containing 2D phase inhomogeneities suppresses the effect of dynamic susceptibility asymmetry and leads to a slight broadening
of the gap in the density of states and a decrease in its depth. Targeted experiments aimed at detecting the effects studied
here would facilitate the development of radio-spectroscopic and optical methods for identifying the presence of inhomogeneities
of various dimensions in multilayer magnetic and optical structures. |
