Dislocation-related absorption and photoluminescence in deformed n-ZnSe crystals

It has been found that the Y-0 line appears in photoluminescence (PL) and absorption of n-ZnSe crystals after plastic deformation. The concept of the dislocation exciton has been used to interpret the results. The binding energy of the dislocation exciton has been determined as 27 meV. It is suggested that dislocation excitons are destroyed by dislocation charge and, therefore, the Y-0 line can be related only to uncharged or slightly charged dislocations. It has also been found that the edge of the absorption spectra of the deformed and undeformed crystals are significantly extended as a result of the Franz-Keldysh effect from charged dislocations. Stress birefringence has also been observed in the deformed crystal.