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arXiv · 1511.08776

A charged quantum dot micropillar system for deterministic light matter interactions

Petros Androvitsaneas·Andrew B. Young·Chritian Schneider·Sebastian Maier·Martin Kamp·Sven Höfling·Sebastian Knauer·Edmund Harbord·Cheng-Yong Hu·John G. Rarity·Ruth Oulton
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Abstract

Quantum dots (QDs) are semiconductor nanostructures in which a three dimensional potential trap produces an electronic quantum confinement, thus mimicking the behaviour of single atomic dipole-like transitions. However unlike atoms, QDs can be incorporated into solid state photonic devices such as cavities or waveguides that enhance the light-matter interaction. A near unit efficiency light-matter interaction is essential for deterministic, scalable quantum information (QI) devices. In this limit, a single photon input into the device will undergo a large rotation of the polarization of the light field due to the strong interaction with the QD. In this paper we measure a macroscopic ($\sim6^o$) phase shift of light as a result of the interaction with a negatively charged QD coupled to a low quality-factor (Q$\sim290$) pillar microcavity. This unexpectedly large rotation angle demonstrates this simple low Q-factor design would enable near deterministic light-matter interactions.

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Petros Androvitsaneas, Andrew B. Young, Chritian Schneider, Sebastian Maier, Martin Kamp, Sven Höfling, Sebastian Knauer, Edmund Harbord, Cheng-Yong Hu, John G. Rarity, Ruth Oulton. 2015-11-27. A charged quantum dot micropillar system for deterministic light matter interactions. https://doi.org/10.1103/physrevb.93.241409

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