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We present a method to include the effects of light excitation on two different models of resonant-tunneling-diode-based devices. Our approach takes into account both photoconductive and charge accumulation effects responsible for shifting the static I–V curve when the structure is under light excitation. Computational simulations led to good agreement between the model and experimental results.

We report the investigation of the steady-state Hall mobility and carrier concentration behavior depending on extrinsic light excitation intensity, wavelength and temperature in n-type liquid-encapsulated Czochralski (LEC) GaAs crystals. The carrier concentration of the samples measured in the dark ranged from 108 to 3×1011 cm−3, and the Hall mobility showed a pronounced minimum in the concentration region 109–1011 cm−3. The measured dependencies demonstrated peculiarities in this region which could not be explained by a homogeneous semiconductor model. We demonstrate that the observed effects are caused by the complex influence of the deep levels in the band gap and of the defect inhomogeneities related to the cellular structure of dislocations. The effect of inhomogeneities is intensified in the samples from the intermediate concentration region 109–1011 cm−3. It is related to the specific compensation conditions, which take place when the Fermi level appears between the EL2 level and the negative-U dou...

The photoelectromagnetic effect is studied in single crystals of CuInSe2. A region of light excitation is found in which the dependence of iPEM on light intensity is linear. From the experimental data, a lifetime of the minority carriers τn=0.6×10−9 sec and a surface recombination velocity s=3×105 cm/sec are determined.