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Optical and transport properties of short period InAs/GaAs superlattices near quantum dot formation

V. A. Kulbachinskii·R. A. Lunin·V. A. Rogozin·V. G. Mokerov·Yu. V. Fedorov·Yu. V. Khabarov·A. de Visser
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Abstract

We have investigated the optical and transport properties of MBE grown short-period superlattices of InAs/GaAs with different numbers of periods (3 <= N <= 24) and a total thickness 14 nm. Bandstructure calculations show that these superlattices represent a quantum well with average composition In_0.16Ga_0.84As. The electron wave functions are only slightly modulated by the superlattice potential as compared to a single quantum well with the same composition, which was grown as a reference sample. The photoluminescence, the resistance, the Shubnikov-de Haas effect and the Hall effect have been measured as a function of the InAs layer thickness Q in the range 0.33 <= Q <= 2.7 monolayers (ML). The electron densities range from 6.8 to 11.5x10^11 cm^-2 for Q <= 2.0 ML. The photoluminescence and magnetotransport data show that only one subband is occupied. When Q >= 2.7 ML quantum dots are formed and the metallic type of conductivity changes to variable range hopping conductivity.

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V. A. Kulbachinskii, R. A. Lunin, V. A. Rogozin, V. G. Mokerov, Yu. V. Fedorov, Yu. V. Khabarov, A. de Visser. 2002-04-25. Optical and transport properties of short period InAs/GaAs superlattices near quantum dot formation. https://doi.org/10.1088/0268-1242%2F17%2F9%2F308

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