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arXiv · 2010.01555

Entangled photon pairs from quantum dots embedded in a self-aligned cavity

Laia Ginés·Carlo Pepe·Junior Gonzales·Niels Gregersen·Sven Höfling·Christian Schneider·Ana Predojević
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Abstract

We introduce a scalable photonic platform that enables efficient generation of entangled photon pairs from a semiconductor quantum dot. Our system, which is based on a self-aligned quantum dot-micro-cavity structure, erases the need for complex steps of lithography and nanofabrication. We experimentally show collection efficiency of 0.17 combined with a Purcell enhancement of up to 1.7 in the pair emission process. We harness the potential of our device to generate photon pairs entangled in time bin, reaching a fidelity of 0.84(5) with the maximally entangled state. The achieved pair collection efficiency is 4 times larger than the state-of-the art. The device, which theoretically supports pair extraction efficiencies of nearly 0.5 is a promising candidate for the implementation of bright sources of time-bin, polarization- and hyper entangled photon pairs in a straightforward manner.

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Laia Ginés, Carlo Pepe, Junior Gonzales, Niels Gregersen, Sven Höfling, Christian Schneider, Ana Predojević. 2020-10-04. Entangled photon pairs from quantum dots embedded in a self-aligned cavity. https://doi.org/10.1364/oe.411021

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