Splitting of channeling-radiation peaks in strained-layer superlattices

Abstract

The peaks in the spectrum of channeling radiation from 106–109-eV electrons traversing crystalline targets are split into two families if the target is a strained-layer superlattice (SLS). We have studied one example of this effect, including the spectral shifts and, especially, the intensity variations that occur when the crystal is rocked. Because of their strong dependence on beam orientation relative to a channel axis, these phenomena should provide a sensitive measure of the strains in the SLS layers as well as of the population of the bound states. Because of the natural widths of the photon peaks in thin layers, good observability will be ensured for superlattice layers with a thickness of several hundred angstroms or more, although in practice this restriction may quite possibly be considerably relaxed, narrow widths not being essential to the observability of the effect.