Influence of electric field on the photoluminescence of silicon nanocrystals

We studied the effect of electric field generated on photoluminescence (PL) of silicon nanocrystals embedded in SiO2 films. We show that the application of electric field generated by means of surface acoustic waves (SAW) results in an increase of the PL intensity of nanocrystal photoluminescence by as much as 10% at a field amplitude of 12 kV/cm at temperatures below 15 K. At temperatures above 20 K the PL intensity decreases as the electric field is applied. The results are discussed within the frame of the self-trapped exciton model.