Abstract

The observation of one-phonon assisted non-radiative spectral transfer¹ is one of the several not well understood features of ruby. Actually, due to the small energy mismatch between Cr³⁺ sites (<1 cm⁻¹), the density of phonon states is low and, more important, destructive interference was expected² because of long wavelength. On such grounds, a two-phonon process should dominate even at low temperature (T<50 K).²

© 1984 Optical Society of America