Transport and entanglement of orbital angular momentum photonic states in turbulent atmosphere

• Applicant: Professor Dr. Andreas Buchleitner
• Subject Area: Optics, Quantum Optics and Physics of Atoms, Molecules and Plasmas
• Term: from 2015 to 2019
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 289382917

• Final Report Year: 2020

Final Report Abstract

We developed a versatile theoretical framework for quantum state transfer in diffractive and refractive media. In particular, we developed analytical and numerical tools to characterise and efficiently simulate the transmission of high-dimensional single and bi-photon quantum states across a turbulent atmosphere, which is an essential ingredient for free space quantum communication technologies. We could show that state of the art adaptive optics techniques allow for a significantly enhanced resilience of free space quantum communication even at moderate turbulence strengths, thus opening novel perspectives for robust quantum state transfer. In addition, we conceived an original method for the efficient theoretical modelling of multiple scattering of intense radiation in dilute clouds of cold atoms, which, by an innovative combination of diagrammatic transport theory with the theory of open quantum systems accounting for the nonlinear atomic response, circumvents the exponential scaling of the atomic Hilbert space with the number of atomic scatterers. We expect that this new approach will find broad applications in the treatment of diverse multiple scattering quantum transport phenomena.

Publications

• Protecting the entanglement of twisted photons by adaptive optics, Phys. Rev. A 97, 012321 (2018)
  N. Leonhard, G. Sorelli, V.N. Shatokhin, C. Reinlein, A. Buchleitner
  (See online at https://doi.org/10.1103/PhysRevA.97.012321)
• Diffraction-induced entanglement loss of orbital-angular-momentum states, Phys. Rev. A 97, 013849 (2018); Erratum Phys. Rev A 99, 019904 (2019)
  G. Sorelli, V.N. Shatokhin, F.S. Roux, A. Buchleitner
  (See online at https://doi.org/10.1103/PhysRevA.99.019904)
• Entanglement protection of high-dimensional states by adaptive optics, New J. Phys. 21, 023003 (2019)
  G. Sorelli, N. Leonhard, V.N. Shatokhin, C. Reinlein, A. Buchleitner
  (See online at https://doi.org/10.1088/1367-2630/ab006e)
• Nonlinear quantum transport of light in a cold atomic cloud, Phys. Rev. A 100, 033816 (2019)
  T. Binninger, V.N. Shatokhin, A. Buchleitner, T. Wellens
  (See online at https://doi.org/10.1103/PhysRevA.100.033816)
• Universal entanglement decay of photonic angular momentum qubit states in atmospheric turbulence: an analytical treatment, J. Phys. A 52, 405303 (2019)
  D. Bachmann, V.N. Shatokhin, A. Buchleitner
  (See online at https://doi.org/10.1088/1751-8121/ab3f3c)
• Entanglement of truncated quantum states, (2020)
  G. Sorelli, V.N. Shatokhin, S.F. Roux, A. Buchleitner
  (See online at https://doi.org/10.1088/2058-9565/ab9417)
• Universal entanglement losses induced by angular uncertainty, J. Opt. 22, 024002 (2020)
  G. Sorelli, V.N. Shatokhin, A. Buchleitner
  (See online at https://doi.org/10.1088/2040-8986/ab66d0)