Light emission due to dislocations in wurtzite ZnO bulk single crystals freshly introduced by plastic deformation

An arbitrary number of dislocations were freshly introduced in wurtzite ZnO bulk single crystals by plastic deformation at high temperatures ( 923 - 1123 K ) , and the optical properties were examined by photoluminescence spectroscopy. ZnO, including a high density (more than 10 9 cm − 2 ) of dislocations, showed excitonic light emission with photon energies of 3.100 and 3.345 eV , as well as their LO-phonon replicas, at a temperature of 11 K , and the intensities increased with increasing dislocation density.