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Title: On-chip beamsplitter operation on single photons from quasi-resonantly excited quantum dots embedded in GaAs rib waveguides

Abstract

We present an on-chip beamsplitter operating on a single-photon level by means of a quasi-resonantly driven InGaAs/GaAs quantum dot. The single photons are guided by rib waveguides and split into two arms by an evanescent field coupler. Although the waveguides themselves support the fundamental TE and TM modes, the measured degree of polarization (∼90%) reveals the main excitation and propagation of the TE mode. We observe the preserved single-photon nature of a quasi-resonantly excited quantum dot by performing a cross-correlation measurement on the two output arms of the beamsplitter. Additionally, the same quantum dot is investigated under resonant excitation, where the same splitting ratio is observed. An autocorrelation measurement with an off-chip beamsplitter on a single output arm reveal the single-photon nature after evanescent coupling inside the on-chip splitter. Due to their robustness, adjustable splitting ratio, and their easy implementation, rib waveguide beamsplitters with embedded quantum dots provide a promising step towards fully integrated quantum circuits.

Authors:
; ; ; ; ; ; ;  [1]
  1. Institut für Halbleiteroptik und Funktionelle Grenzflächen and Research Center SCoPE, University of Stuttgart, Allmandring 3, 70569 Stuttgart (Germany)
Publication Date:
OSTI Identifier:
22482263
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 107; Journal Issue: 2; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; EXCITATION; GALLIUM ARSENIDES; INDIUM ARSENIDES; OPERATION; PHOTONS; POLARIZATION; QUANTUM DOTS; WAVEGUIDES

Citation Formats

Rengstl, U., Schwartz, M., Herzog, T., Hargart, F., Paul, M., Portalupi, S. L., Jetter, M., and Michler, P., E-mail: p.michler@ihfg.uni-stuttgart.de. On-chip beamsplitter operation on single photons from quasi-resonantly excited quantum dots embedded in GaAs rib waveguides. United States: N. p., 2015. Web. doi:10.1063/1.4926729.
Rengstl, U., Schwartz, M., Herzog, T., Hargart, F., Paul, M., Portalupi, S. L., Jetter, M., & Michler, P., E-mail: p.michler@ihfg.uni-stuttgart.de. On-chip beamsplitter operation on single photons from quasi-resonantly excited quantum dots embedded in GaAs rib waveguides. United States. doi:10.1063/1.4926729.
Rengstl, U., Schwartz, M., Herzog, T., Hargart, F., Paul, M., Portalupi, S. L., Jetter, M., and Michler, P., E-mail: p.michler@ihfg.uni-stuttgart.de. Mon . "On-chip beamsplitter operation on single photons from quasi-resonantly excited quantum dots embedded in GaAs rib waveguides". United States. doi:10.1063/1.4926729.
@article{osti_22482263,
title = {On-chip beamsplitter operation on single photons from quasi-resonantly excited quantum dots embedded in GaAs rib waveguides},
author = {Rengstl, U. and Schwartz, M. and Herzog, T. and Hargart, F. and Paul, M. and Portalupi, S. L. and Jetter, M. and Michler, P., E-mail: p.michler@ihfg.uni-stuttgart.de},
abstractNote = {We present an on-chip beamsplitter operating on a single-photon level by means of a quasi-resonantly driven InGaAs/GaAs quantum dot. The single photons are guided by rib waveguides and split into two arms by an evanescent field coupler. Although the waveguides themselves support the fundamental TE and TM modes, the measured degree of polarization (∼90%) reveals the main excitation and propagation of the TE mode. We observe the preserved single-photon nature of a quasi-resonantly excited quantum dot by performing a cross-correlation measurement on the two output arms of the beamsplitter. Additionally, the same quantum dot is investigated under resonant excitation, where the same splitting ratio is observed. An autocorrelation measurement with an off-chip beamsplitter on a single output arm reveal the single-photon nature after evanescent coupling inside the on-chip splitter. Due to their robustness, adjustable splitting ratio, and their easy implementation, rib waveguide beamsplitters with embedded quantum dots provide a promising step towards fully integrated quantum circuits.},
doi = {10.1063/1.4926729},
journal = {Applied Physics Letters},
number = 2,
volume = 107,
place = {United States},
year = {Mon Jul 13 00:00:00 EDT 2015},
month = {Mon Jul 13 00:00:00 EDT 2015}
}
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