SIZE-SELECTIVE PHOTOLUMINESCENCE EXCITATION SPECTROSCOPY IN CDSE NANOCRYSTALS

We present a photoluminescence excitation study of CdSe nanocrystals e mbedded in a silicate glass matrix. The band edge emission was found t o be strongly dependent on the excitation photon energy (hv(L)) when h v(L) is much higher than the fundamental absorption peak. Using the th eoretical energies ES electronic states in CdSe nanocrystal calculated by Ekimov et al. [J. Opt. Sec. Am. B 10, 100 (1993)] we showed our re sults can be understood as a size-selective effect. We also show that it is possible to use such excitation spectroscopy to determine the ex cited state energies and also the size distribution in nanocrystal sam ples.