07.12.2016
Lecture A.A. Semenov and D. Vasylyev  "Nonclassical Light in the Atmosphere: EllipticBeam Model and Gaussian Entanglement"
Institut für Physik, Universität Rostock, Germany
Organiser: Max Planck Institute for the Science of Light
Title: Nonclassical Light in the Atmosphere: EllipticBeam Model and Gaussian Entanglement
Time, place: Wednesday, December 7, 2016, 3 p.m. Small Seminar room A.2.500, Staudtstr. 2
Abstract: Atmospheric channels are promising candidates for establishing global quantum communications. Atmospheric turbulence randomly modiﬁes light beams, which results in random ﬂuctuations of the aperture transmittance. We discuss a theoretical model, the ellipticbeam approximation, which describes probability distributions of the transmittance [1]. This model includes such eﬀects as beam wandering and elliptic beam deformations. The theoretical results are in good agreement with experiments in weak and weaktomoderate atmospheric channels [2], including the experimental transmission of quadrature squeezing through the atmosphere [3]. Proper results are also obtained for strongturbulence conditions. As an application of the theory, we consider the transmission of Gaussian entangled states through atmospheric channels [4]. We have proposed a protocol, which enables one to preserve Gaussian entanglement in the turbulent atmosphere. [1] D. Vasylyev, A.A. Semenov, and W. Vogel Phys. Rev. Lett. 117, 090501 (2016). [2] V. C. Usenko, B. Heim, C. Peuntinger, C. Wittmann, C. Marquardt, G. Leuchs, and R. Filip, New J. Phys. 14, 093048 (2012). [3] C. Peuntinger, B. Heim, Ch. M¨uller, Ch. Gabriel, Ch. Marquardt, and G. Leuchs, Phys. Rev. Lett. 113, 060502 (2014).[4] M. Bohmann, A. A. Semenov, J. Sperling, and W. Vogel Phys. Rev. A 94, 010302(R) (2016).
