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arXiv · 1611.08911

Quantitative strain analysis of InAs/GaAs quantum dot materials

Per Erik Vullum·Magnus Nord·Maryam Vatanparast·Sedsel Fretheim Thomassen·Chris Boothroyd·Randi Holmestad·Bjorn-Ove Fimland·Turid Worren Reenaas
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Abstract

Geometric phase analysis has been applied to high resolution aberration corrected (scanning) transmission electron microscopy images of InAs/GaAs quantum dot (QD) materials. We show quantitatively how the lattice mismatch induced strain varies on the atomic scale and tetragonally distorts the lattice in a wide region that extends several nanometers into the GaAs spacer layer below and above the QDs. Finally, we show how V-shaped dislocations originating at the QD/GaAs interface efficiently remove most of the lattice mismatch induced tetragonal distortions in and around the QD.

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Per Erik Vullum, Magnus Nord, Maryam Vatanparast, Sedsel Fretheim Thomassen, Chris Boothroyd, Randi Holmestad, Bjorn-Ove Fimland, Turid Worren Reenaas. 2016-11-27. Quantitative strain analysis of InAs/GaAs quantum dot materials. https://arxiv.org/abs/1611.08911

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