Auger decay of degenerate and Bose-condensed excitons in Cu${}_2$O

Abstract

We study the non-radiative Auger decay of excitons in Cu${}_2$O, in which two excitons scatter to an excited electron and hole. The exciton decay rate for the direct and the phonon-assisted processes is calculated from first principles; incorporating the band structure of the material leads to a relatively shorter lifetime of the triplet state ortho excitons. We compare our results with the Auger decay rate extracted from data on highly degenerate triplet excitons and Bose-condensed singlet excitons in Cu${}_2$O.

15 pages, revtex, figures available from G. Kavoulakis