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Abstract: We have carried out thermally stimulated current measurements on as-grown Tl2InGaS4-layered single crystals in the low temperature range 10–60K with different heating rates. We found experimental evidence for the presence of two shallow hole trapping centers with activation energies of 4 and 10meV. We have determined the trap parameters using various methods of analysis, and these agree with each other. Their capture cross-sections have been found to be 6.5×10−26 and 4.0×10−25 cm2, respectively, and their concentrations are 2.1×1012 and 6.5×1012 cm−3, respectively. It is concluded that in these centers retrapping is negligible, as confirmed by the good agreement between the experimental results and the theoretical predictions of the model that assumes slow retrapping. [Copyright &y& Elsevier]

Thermally stimulated current measurements are carried out on as-grown TlGaSe2 layered single crystals in the temperature range of 90–220 K with various heating rates. Experimental evidence is found for the presence of two trapping centers with activation energy 98 and 130 meV. The retrapping process is negligible for these levels, as confirmed by good agreement between the experimental results and theoretical predictions of the model that assumes slow retrapping. The calculation yielded 2.3×10−24 and 1.8×10−24 cm2 for the capture cross section and 1.4×1014 and 3.8×1014 cm−3 for the concentration of the traps studied. [Copyright &y& Elsevier]

We demonstrate dual-wavelength short pulses lasing at 1540 and 1675 nm based on a silicon waveguide. The inline silicon waveguide inside a laser cavity facilitates pulse compression and laser mode-locking due to two-photon absorption (TPA) and TPA-induced free-carrier absorption at 1540 nm. Compressed pulses provide pump for stimulated Raman scattering. Raman amplification and low threshold Raman lasing are observed based on the same silicon waveguide. [ABSTRACT FROM PUBLISHER]