AN OPTICALLY DETECTED MAGNETIC-RESONANCE STUDY OF LASER-ABLATION GROWN PBI2 EPITAXIAL-FILMS

Epitaxial films of PbI2 were grown by the laser ablation technique. Th e correlation between certain emission processes and lattice imperfect ions was examined, utilizing optically detected magnetic resonance (OD MR) spectroscopy. The present work focuses on the characterization of the nonexcitonic green and red emission bands. The results suggested t hat these emission processes are associated with a common donor state. Moreover, this donor state is participating also in nonradiative dono r-acceptor recombination process. The quenching in luminescence intens ity, pronounced in the ODMR measurement, indicates that the experiment detected actually the nonradiative recombination. Thus, the ODMR meas urements identified a hole trapped at an isotropic nonradiative accept or site with g(h) approximate to 2.05, that corresponds to the lead va cancy defect, [V-](Pb+2) . The photogenerated electron is trapped in a n anisotropic radiative donor site with g(ell) approximate to 2.34 and g(e.l.) approximate to 1.73,associated with the iodine vacancy, [V-0] (iodine).