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arXiv · 1406.7670

Extremely low inhomogeneous broadening of exciton lines in shallow (In,Ga)As/GaAs quantum wells

S. V. Poltavtsev·Yu. P. Efimov·Yu. K. Dolgikh·S. A. Eliseev·V. V. Petrov·V. V. Ovsyankin
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Abstract

We study radiative linewidth of exciton resonance in shallow In$_x$Ga$_{1-x}$As/GaAs single quantum wells as a function of indium concentration in the range $x=0.02...0.10$ and well thickness in the range $L_Z=1...30$ nm using the method of Brewster reflection spectroscopy. Record linewidths of heavy-hole exciton resonance of about 130...180 $μ$eV are measured in reflection spectra for single quantum wells with $L_Z=2$ nm and $x=0.02$ at temperature 9 K. In these spectra, the non-radiative linewidth including inhomogeneous broadening can be comparable or even less than radiative linewidth. It is shown that radiative linewidth weakly depends on $x$ and $L_Z$ in these ranges. In multiple-quantum-well Bragg structure with ten periods radiative linewidth exceeds inhomogeneous broadening by 4 times.

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S. V. Poltavtsev, Yu. P. Efimov, Yu. K. Dolgikh, S. A. Eliseev, V. V. Petrov, V. V. Ovsyankin. 2014-06-30. Extremely low inhomogeneous broadening of exciton lines in shallow (In,Ga)As/GaAs quantum wells. https://doi.org/10.1016/j.ssc.2014.09.005

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