Excitation of deep centers via nitrogen impurity in GaP single crystals

Consideration is given to the results of complex studies of fine structure of excitation spectra and polarization characteristics of photoluminescence bands with ℎνmax = 1.68 and 2.21 eV in n-GaP single crystals. Laser spectroscopy of excitation was used to establish the existence of complex centers, including isoelectron pairs of nitrogen atoms NNi (i=4.5) and deep luminescence centers (ℎνmax=1.68 eV). It is shown that NNi-pairs in such centers are responsible for processes of photoluminescence excitation. Method of polarization diagrams was used to prove the absence of correlation in mutual orientation of optical dipoles, connected with different components of revealed complex centers