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Title: On-chip interference of single photons from an embedded quantum dot and an external laser

Abstract

In this work, we demonstrate the on-chip two-photon interference between single photons emitted by a single self-assembled InGaAs quantum dot and an external laser. The quantum dot is embedded within one arm of an air-clad directional coupler which acts as a beam-splitter for incoming light. Photons originating from an attenuated external laser are coupled to the second arm of the beam-splitter and then combined with the quantum dot photons, giving rise to two-photon quantum interference between dissimilar sources. We verify the occurrence of on-chip Hong-Ou-Mandel interference by cross-correlating the optical signal from the separate output ports of the directional coupler. This experimental approach allows us to use a classical light source (laser) to assess in a single step the overall device performance in the quantum regime and probe quantum dot photon indistinguishability on application realistic time scales.

Authors:
; ; ; ; ; ;  [1];  [2]
  1. Department of Physics and Astronomy, University of Sheffield, Sheffield S3 7RH (United Kingdom)
  2. Department of Electronic and Electrical Engineering, University of Sheffield, Sheffield S1 3JD (United Kingdom)
Publication Date:
OSTI Identifier:
22590810
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 108; Journal Issue: 25; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; AIR; BEAMS; EQUIPMENT; GALLIUM ARSENIDES; INDIUM ARSENIDES; INTERFERENCE; LASERS; LIGHT SOURCES; PERFORMANCE; PHOTONS; PROBES; QUANTUM DOTS; SIGNALS; VISIBLE RADIATION

Citation Formats

Prtljaga, N., E-mail: n.prtljaga@sheffield.ac.uk, Bentham, C., O'Hara, J., Royall, B., Wilson, L. R., Skolnick, M. S., Fox, A. M., and Clarke, E. On-chip interference of single photons from an embedded quantum dot and an external laser. United States: N. p., 2016. Web. doi:10.1063/1.4954220.
Prtljaga, N., E-mail: n.prtljaga@sheffield.ac.uk, Bentham, C., O'Hara, J., Royall, B., Wilson, L. R., Skolnick, M. S., Fox, A. M., & Clarke, E. On-chip interference of single photons from an embedded quantum dot and an external laser. United States. doi:10.1063/1.4954220.
Prtljaga, N., E-mail: n.prtljaga@sheffield.ac.uk, Bentham, C., O'Hara, J., Royall, B., Wilson, L. R., Skolnick, M. S., Fox, A. M., and Clarke, E. Mon . "On-chip interference of single photons from an embedded quantum dot and an external laser". United States. doi:10.1063/1.4954220.
@article{osti_22590810,
title = {On-chip interference of single photons from an embedded quantum dot and an external laser},
author = {Prtljaga, N., E-mail: n.prtljaga@sheffield.ac.uk and Bentham, C. and O'Hara, J. and Royall, B. and Wilson, L. R. and Skolnick, M. S. and Fox, A. M. and Clarke, E.},
abstractNote = {In this work, we demonstrate the on-chip two-photon interference between single photons emitted by a single self-assembled InGaAs quantum dot and an external laser. The quantum dot is embedded within one arm of an air-clad directional coupler which acts as a beam-splitter for incoming light. Photons originating from an attenuated external laser are coupled to the second arm of the beam-splitter and then combined with the quantum dot photons, giving rise to two-photon quantum interference between dissimilar sources. We verify the occurrence of on-chip Hong-Ou-Mandel interference by cross-correlating the optical signal from the separate output ports of the directional coupler. This experimental approach allows us to use a classical light source (laser) to assess in a single step the overall device performance in the quantum regime and probe quantum dot photon indistinguishability on application realistic time scales.},
doi = {10.1063/1.4954220},
journal = {Applied Physics Letters},
number = 25,
volume = 108,
place = {United States},
year = {Mon Jun 20 00:00:00 EDT 2016},
month = {Mon Jun 20 00:00:00 EDT 2016}
}
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