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arXiv · 1805.10623

A deterministically fabricated spectrally-tunable quantum dot based single-photon source

S. Fischbach·M. v. Helversen·M. Schmidt·A. Kaganskiy·R. Schmidt·A. Schliwa·T. Heindel·S. Rodt·S. Reitzenstein
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Abstract

Spectrally-tunable quantum-light sources are key elements for the realization of long-distance quantum communication. A deterministically fabricated single-photon source with a photon-extraction efficiency of {\eta}=(20 +- 2) % and a tuning range of {\Delta}E=2.5 meV is presented here. The device consists of a single pre-selected quantum dot monolithically integrated into a microlens which is bonded onto a piezoelectric actuator via thermocompression goldbonding. The thin gold layer simultaneously acts as a backside mirror for the quantum dot emission, which is efficiently extracted from the device by an optimized lens structure patterned via 3D in-situ electron-beam lithography. The single-photon nature of the emission is proven by photon-autocorrelation measurements with $g^{(2)}$ ({\tau}=0)=0.04 +- 0.02. The combination of deterministic fabrication, spectral-tunability and high broadband photon-extraction efficiency makes the microlens single-photon source an interesting building block towards the realization of quantum repeaters networks.

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S. Fischbach, M. v. Helversen, M. Schmidt, A. Kaganskiy, R. Schmidt, A. Schliwa, T. Heindel, S. Rodt, S. Reitzenstein. 2018-05-27. A deterministically fabricated spectrally-tunable quantum dot based single-photon source. https://arxiv.org/abs/1805.10623

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