Infrared Lateral Photoconductivity of InGaAs Quantum Dots: the Temperature Dependence
L.D. Moldavskaya, V.I. Shashkin, M.N. Drozdov, V.M. Daniltsev, A.V. Antonov and A.N. Yablonsky
Institute for Physics of Microstructures, Russian Academy of Sciences Nizhni Novgorod, Russia
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We report the temperature dependence of lateral infrared photoconductivity in multilayer InGaAs/GaAs heterostructures with selectively doped quantum dots fabricated by metalorganic chemical vapor deposition. Two spectral lines of normal-incidence intersubband photoconductivity (90 meV and 230 meV) and a line originating from interband transitions (930 meV) were observed. The photoconductivity line 230 meV is revealed up to the temperature 140 K. The long-wavelength photoconductivity line 90 meV is quenched rapidly at the temperature 30÷40 K owing to redistribution of photoexcited carriers between small and large dots. The obtained results confirm the hypothesis about bimodal distribution of quantum dot sizes.
DOI: 10.12693/APhysPolA.103.579
PACS numbers: 78.30.Fs, 78.55.Cr, 78.66.Fd