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arXiv · 1406.7676

Polaron-induced lattice distortion of (In,Ga)As quantum dots by optically excited carriers

Sebastian Tiemeyer·Michael Bombeck·Michael Paulus·Christian Sternemann·Julia Nase·Holger Göhring·Florian J. Wirkert·Johannes Möller·Thomas Büning·Oliver H. Seeck·Dirk Reuter·Andreas D. Wieck·Manfred Bayer·Metin Tolan
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Abstract

We report on a high resolution x-ray diffraction study unveiling the effect of carriers optically injected into (In,Ga)As quantum dots on the surrounding GaAs crystal matrix. We find a tetragonal lattice expansion with enhanced elongation along the [001] crystal axis that is superimposed on an isotropic lattice extension. The isotropic contribution arises from excitation induced lattice heating as confirmed by temperature dependent reference studies. The tetragonal expansion on the femtometer scale is attributed to polaron formation by carriers trapped in the quantum dots.

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Sebastian Tiemeyer, Michael Bombeck, Michael Paulus, Christian Sternemann, Julia Nase, Holger Göhring, Florian J. Wirkert, Johannes Möller, Thomas Büning, Oliver H. Seeck, Dirk Reuter, Andreas D. Wieck, Manfred Bayer, Metin Tolan. 2014-06-30. Polaron-induced lattice distortion of (In,Ga)As quantum dots by optically excited carriers. https://arxiv.org/abs/1406.7676

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