1
|
Jöns KD, Schweickert L, Versteegh MAM, Dalacu D, Poole PJ, Gulinatti A, Giudice A, Zwiller V, Reimer ME. Bright nanoscale source of deterministic entangled photon pairs violating Bell's inequality. Sci Rep 2017; 7:1700. [PMID: 28490728 PMCID: PMC5475295 DOI: 10.1038/s41598-017-01509-6] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2017] [Accepted: 03/28/2017] [Indexed: 11/18/2022] Open
Abstract
Global, secure quantum channels will require efficient distribution of entangled photons. Long distance, low-loss interconnects can only be realized using photons as quantum information carriers. However, a quantum light source combining both high qubit fidelity and on-demand bright emission has proven elusive. Here, we show a bright photonic nanostructure generating polarization-entangled photon pairs that strongly violates Bell’s inequality. A highly symmetric InAsP quantum dot generating entangled photons is encapsulated in a tapered nanowire waveguide to ensure directional emission and efficient light extraction. We collect ~200 kHz entangled photon pairs at the first lens under 80 MHz pulsed excitation, which is a 20 times enhancement as compared to a bare quantum dot without a photonic nanostructure. The performed Bell test using the Clauser-Horne-Shimony-Holt inequality reveals a clear violation (SCHSH > 2) by up to 9.3 standard deviations. By using a novel quasi-resonant excitation scheme at the wurtzite InP nanowire resonance to reduce multi-photon emission, the entanglement fidelity (F = 0.817 ± 0.002) is further enhanced without temporal post-selection, allowing for the violation of Bell’s inequality in the rectilinear-circular basis by 25 standard deviations. Our results on nanowire-based quantum light sources highlight their potential application in secure data communication utilizing measurement-device-independent quantum key distribution and quantum repeater protocols.
Collapse
Affiliation(s)
- Klaus D Jöns
- Applied Physics Department, Royal Institute of Technology, Albanova University Centre, Roslagstullsbacken 21, 106 91, Stockholm, Sweden. .,Kavli Institute of Nanoscience, Delft University of Technology, Lorentzweg 1, 2628CJ, Delft, The Netherlands.
| | - Lucas Schweickert
- Applied Physics Department, Royal Institute of Technology, Albanova University Centre, Roslagstullsbacken 21, 106 91, Stockholm, Sweden.,Kavli Institute of Nanoscience, Delft University of Technology, Lorentzweg 1, 2628CJ, Delft, The Netherlands
| | - Marijn A M Versteegh
- Applied Physics Department, Royal Institute of Technology, Albanova University Centre, Roslagstullsbacken 21, 106 91, Stockholm, Sweden.,Kavli Institute of Nanoscience, Delft University of Technology, Lorentzweg 1, 2628CJ, Delft, The Netherlands.,Quantum optics, Quantum Nanophysics and Quantum Information, Faculty of Physics, University of Vienna, Boltzmanngasse 5, 1090, Vienna, Austria.,Institute for Quantum Optics and Quantum Information, Austrian Academy of Science, Boltzmanngasse 3, 1090, Vienna, Austria
| | - Dan Dalacu
- National Research Council of Canada, Ottawa, K1A 0R6, Canada
| | - Philip J Poole
- National Research Council of Canada, Ottawa, K1A 0R6, Canada
| | - Angelo Gulinatti
- Politecnico di Milano, Dipartimento di Elettronica Informazione e Bioingegneria, piazza Leonardo da Vinci 32, 20133, Milano, Italy
| | - Andrea Giudice
- Micro Photon Devices, via Stradivari 4, 39100, Bolzano, Italy
| | - Val Zwiller
- Applied Physics Department, Royal Institute of Technology, Albanova University Centre, Roslagstullsbacken 21, 106 91, Stockholm, Sweden.,Kavli Institute of Nanoscience, Delft University of Technology, Lorentzweg 1, 2628CJ, Delft, The Netherlands
| | - Michael E Reimer
- Kavli Institute of Nanoscience, Delft University of Technology, Lorentzweg 1, 2628CJ, Delft, The Netherlands.,Institute for Quantum Computing and Department of Electrical & Computer Engineering, University of Waterloo, Waterloo, N2L 3G1, Canada
| |
Collapse
|