Stabilization of transmittance fluctuations caused by beam wandering in continuous-variable quantum communication over free-space atmospheric channels

Usenko VC, Peuntinger C, Heim B, Guenthner K, Derkach I, Elser D, Marquardt C, Filip R, Leuchs G (2018)

Publication Type: Journal article

Publication year: 2018

Journal

Optics Express Optical Society of America

Book Volume: 26

Pages Range: 31106-31115

Journal Issue: 24

DOI: 10.1364/OE.26.031106

Abstract

Transmittance fluctuations in turbulent atmospheric channels result in quadrature excess noise which limits applicability of continuous-variable quantum communication. Such fluctuations are commonly caused by beam wandering around the receiving aperture. We study the possibility to stabilize the fluctuations by expanding the beam, and test this channel stabilization in regard of continuous-variable entanglement sharing and quantum key distribution. We perform transmittance measurements of a real free-space atmospheric channel for different beam widths and show that the beam expansion reduces the fluctuations of the channel transmittance by the cost of an increased overall loss. We also theoretically study the possibility to share an entangled state or to establish secure quantum key distribution over the turbulent atmospheric channels with varying beam widths. We show the positive effect of channel stabilization by beam expansion on continuous-variable quantum communication as well as the necessity to optimize the method in order to maximize the secret key rate or the amount of shared entanglement. Being autonomous and not requiring adaptive control of the source and detectors based on characterization of beam wandering, the method of beam expansion can be also combined with other methods aiming at stabilizing the fluctuating free-space atmospheric channels.

Authors with CRIS profile

Christoph Marquardt Institut für Optik, Information und Photonik Gerhard Leuchs Lehrstuhl für Experimentalphysik (Optik)

Involved external institutions

Max-Planck-Institut für die Physik des Lichts (MPL) / Max Planck Institute for the Science of Light DE Germany (DE) Palacky University Olomouc / Univerzita Palackého v Olomouci CZ Czech Republic (CZ)

How to cite

APA:

Usenko, V.C., Peuntinger, C., Heim, B., Guenthner, K., Derkach, I., Elser, D.,... Leuchs, G. (2018). Stabilization of transmittance fluctuations caused by beam wandering in continuous-variable quantum communication over free-space atmospheric channels. Optics Express, 26(24), 31106-31115. https://doi.org/10.1364/OE.26.031106

MLA:

Usenko, Vladyslav C., et al. "Stabilization of transmittance fluctuations caused by beam wandering in continuous-variable quantum communication over free-space atmospheric channels." Optics Express 26.24 (2018): 31106-31115.

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