A quantum dot in a microcavity as a bright source of coherent single photons

Tomm, Natasha. A quantum dot in a microcavity as a bright source of coherent single photons. 2021, Doctoral Thesis, University of Basel, Faculty of Science.

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Official URL: https://edoc.unibas.ch/84050/

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A single photon source is an enabling technology in device-independent quantum communication, quantum simulation, linear optics-based and measurement-based quantum computing. These applications employ many photons and place stringent requirements on the efficiency of single photon creation. The scaling on efficiency is typically an exponential function of the number of photons. Schemes taking full advantage of quantum superposition also depend sensitively on the coherence of the photons, i.e. their indistinguishability.
This thesis reports a single-photon source with a high end-to-end efficiency. We employ gated quantum dots in an open, tunable microcavity. The gating provides control of the charge and electrical tuning of the emission frequency, the high-quality material and careful design of the system ensures low noise, and the tunability of the microcavity compensates for the lack of control in quantum dot position and emission frequency. Transmission through the top mirror is the dominant escape route for photons from the microcavity, and this output is well-matched to a single-mode fiber. With this design, we can create a single photon at the output of the final optical fiber on-demand with a probability of 57% and with an average two-photon interference visibility of 97.5%. Coherence persists in trains of thousands of photons with single photon creation at a repetition rate of 1 GHz.
Advisors:Warburton, Richard J
Committee Members:Treutlein, Philipp and Löffler, Wolfgang
Faculties and Departments:05 Faculty of Science > Departement Physik > Physik > Experimental Physics (Warburton)
UniBasel Contributors:Treutlein, Philipp
Item Type:Thesis
Thesis Subtype:Doctoral Thesis
Thesis no:14223
Thesis status:Complete
Number of Pages:120
Identification Number:
  • urn: urn:nbn:ch:bel-bau-diss142236
edoc DOI:
Last Modified:17 Aug 2021 04:30
Deposited On:16 Aug 2021 13:14

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