arXiv:1405.3765 · Nano Letters

Polarization Entangled Photons from Quantum Dots Embedded in Nanowires

Tobias Huber, Ana Predojević, Milad Khoshnegar, Dan Dalacu, Philip J. Poole, Hamed Majedi, Gregor Weihs

Published Nov 14, 2014• 89 citations

Abstract

In this Letter, we present entanglement generated from a novel structure: a single InAsP quantum dot embedded in an InP nanowire. These structures can grow in a site-controlled way and exhibit high collection efficiency; we detect 0.5 million biexciton counts per second coupled into a single mode fiber with a standard commercial avalanche photo diode. If we correct for the known setup losses and detector efficiency, we get an extraction efficiency of 15(3) %. For the measured polarization entanglement, we observe a fidelity of 0.76(2) to a reference maximally entangled state as well as a concurrence of 0.57(6).

DOI: 10.1021/nl503581d

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