Generation of Lattice Defects by Exciton Interaction in RbI: Lattice Instability under Dense Electronic Excitation

Abstract
We found that dense electronic excitation of RbI at 4.2 K by two-photon absorption produces the F band and a new luminescence band, of which the intensities are proportional to the square of the density of excitation. Such creation of F centers and new luminescence centers has been shown to arise from interaction between free excitons and self-trapped excitons.