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Optical Method for Determination of Carrier Density in Modulation Doped Quantum Wells

G. V. Astakhov·V. P. Kochereshko·D. R. Yakovlev·W. Ossau·J. Nurnberger·W. Faschinger·G. Landwehr·T. Wojtowicz·G. Karczewski·J. Kossut
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Abstract

An optical method is suggested to determine the concentration of two-dimensional electrons in modulation-doped quantum wells at low and moderate electron densities between 10^{9} and 2x10^{11} cm^{-2}. The method is based on an analysis of magneto-reflectivity spectra of charged excitons (trions). The circular polarization degree and the oscillator strength of the charged excitons contain information about the density and spin polarization of two-dimensional electron gas. The method is applied to CdTe/(Cd,Mg)Te and ZnSe/Zn,Mg)(S,Se) heterostructures.

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G. V. Astakhov, V. P. Kochereshko, D. R. Yakovlev, W. Ossau, J. Nurnberger, W. Faschinger, G. Landwehr, T. Wojtowicz, G. Karczewski, J. Kossut. 2001-11-30. Optical Method for Determination of Carrier Density in Modulation Doped Quantum Wells. https://doi.org/10.1103/physrevb.65.115310

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