Abstract
HgI 2 microcrystallites are grown on porous polymer matrices. It is observed that the morphology and the optical spectra of the HgI 2 microcrystallites change depending on the dose cycles of the acetone solution of HgI 2 . Under the low excitation density of ∼5 v; mW/cm 2 , nonlinear luminescence due to the many-body effects of excitons appears on high dose samples. An exciton accumulation by an effective energy transfer from the matrices occurs and makes the many-body effects possible under such low-density excitation.