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Formation of nanostructured TiO2 by femtosecond laser irradiation of titanium in O2 J. Appl. Phys. 112, 063108 (2012) Ultralow-power local laser control of the dimer density in alkali-metal vapors through photodesorption Appl. Phys. Lett. 101, 091107 (2012) Optical absorption of silicon nanowires J. Appl. Phys. 112, 033506 (2012) Crystallization of fused silica surfaces by ultra-violet laser irradiation J. Appl. Phys. 112, 023118 (2012) Mechanism for atmosphere dependence of laser damage morphology in HfO2/SiO2 high reflective films Micro-Raman spectroscopy has been applied to investigate the impact of laser irradiation on semiconducting CdTe/ZnTe quantum dots (QDs) structures. A reference sample (without dots) was also studied for comparison. Both samples were grown by molecular beam epitaxy technique on the p-type GaAs substrate. The Raman spectra have been recorded for different time of a laser exposure and for various laser powers. The spectra for both samples exhibit peak related to the localized longitudinal (LO) ZnTe phonon of a wavenumber equal to 210 cm À1 . For the QD sample, a broad band corresponding to the LO CdTe phonon related to the QD-layer appears at a wavenumber of 160 cm À1 . With increasing time of a laser beam exposure and laser power, the spectra get dominated by tellurium-related peaks appearing at wavenumbers around 120 cm À1 and 140 cm À1 . Simultaneously, the ZnTe surface undergoes rising damage, with the formation of Te aggregates at the pinhole edge as reveal atomic force microscopy observations. Local temperature of irradiated region has been estimated from the anti-Stokes/Stokes ratio of the Te modes intensity and it was found to be close or exceeding ZnTe melting point. Thus, the laser damage can be explained by the ablation process. V C 2012 American Institute of Physics.

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