Exciton and pair recombination in crystalline and amorphous As2Se3

For the first time it has been possible to compare by ODMR the recombination processes in amorphous and crystalline forms of a semiconductor. The results show that in c- and a-As2Se3 the same defects are involved in exciton and distant pair recombination. A direct comparison of the ODMR signal strength and the PL fatigue in the glass shows that the resonances are from radiative centres.