NONLINEAR SPECTROSCOPY OF OXIDIZED CUINS2 NANOCRYSTALS

The pump-and-probe method was used in the picosecond range to study no nlinear absorption in oxidised CuInS2 nanocrystals (of 3 Mn radius) em bedded in a polymer film. Oxidation gave rise to an additional absorpt ion band with its maximum at 1.03 eV. This band was bleached by excita tion with laser pulses of the 1.08 mu m wavelength. Fast (similar to 5 0 ps) capture of carriers by deep trapping states resulted in long-liv ed (in excess of 300 ps) bleaching and induced absorption. An energy l evel diagram was proposed for oxidised CuInS2 nanocrystals.