HOLE-FILLING OF PERSISTENT SPECTRAL HOLES IN THE EXCITONIC ABSORPTION-BAND OF CUBR QUANTUM DOTS

Persistent spectral-holes (p-SH) are burned in the Z(1,2) excitonic ba nd of CuBr nanocrystals by a pulsed laser excitation. The annealing of p-SH is studied by three types of hole-filling (HF) experiments: (i) the spontaneous HF, (ii) thermally-induced HF, and (iii) the laser-ind uced HF. Results are compared to the well developed theory of the pers istent spectral hole-burning (p-SHB) in the system of molecules in amo rphous matrices. Both p-SHB and HF phenomena can be explained within t he framework of a photochemical reaction like the photoionization of n anocrystals. The potential application of p-SHB to the frequency-domai n optical data storage is discussed. (C) 1997 American Institute of Ph ysics.