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arXiv · 1804.02758

In-situ tuning of individual position-controlled nanowire quantum dots via laser-induced intermixing

Alexis Fiset-Cyr·Dan Dalacu·Sofiane Haffouz·Philip J. Poole·Jean Lapointe·Geof C. Aers·Robin L. William
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Abstract

We demonstrate an in-situ technique to tune the emission energy of semiconductor quantum dots. The technique is based on laser-induced atomic intermixing applied to nanowire quantum dots grown using a site-selective process that allows for the deterministic tuning of individual emitters. A tuning range of up to 15 meV is obtained with a precision limited by the laser exposure time. A distinct saturation of the energy shift is observed, which suggests an intermixing mechanism relying on grown-in defects that are subsequently removed from the semiconductor material during annealing. The ability to tune different emitters into resonance with each other will be required for fabricating remote quantum dot-based sources of indistinguishable photons for secure quantum networks.

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Alexis Fiset-Cyr, Dan Dalacu, Sofiane Haffouz, Philip J. Poole, Jean Lapointe, Geof C. Aers, Robin L. William. 2018-04-08. In-situ tuning of individual position-controlled nanowire quantum dots via laser-induced intermixing. https://doi.org/10.1063/1.5040268

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