Full Characterization of the Quantum Effects of Light after Transmission through the Atmosphere

• Applicant: Professor Dr. Werner Vogel
• Subject Area: Optics, Quantum Optics and Physics of Atoms, Molecules and Plasmas
• Term: from 2014 to 2021
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 263972363

The main purpose of the proposed project prolongation is the ''Full Characterization of the Quantum Effects of Light after Transmission through the Atmosphere'' and is based on our first proposal. Therefore, we will continue developing efficient techniques for characterizing the quantum state of light under atmospheric conditions. The research plan of the 18 months of prolongation period is structured into the main parts of atmospheric turbulence effects on multipartite nonclassicality and multipartite entanglement.First, we want to further develop our characterization techniques for nonclassical radiation properties after passing through a turbulent medium. In this context, we will adapt the method of multi-mode nonclassical moments to the case of atmospheric turbulent loss. Furthermore, we plan to investigate multipartite nonclassicality quasiprobabilities of light, which contain the full information on the quantum state. These methods may require to reformulate existing measurement strategies, to optimize them for atmospheric conditions. Second, we will generalize our studies of entanglement of radiation fields in atmospheric channels. The anticipated initial step is a generalization of our previous treatment of entanglement in turbulent loss media to multipartite scenarios. For that purpose we will adapt our construction methods of multipartite entanglement witnesses to infer multipartite quantum correlations of states after propagation through fluctuating-loss channels. The results of this second funding period will complement our theoretical analysis of quantum effects in the turbulent atmosphere and it will result in a deeper understanding of the impact of fluctuating losses in quantum optical free-space links. In particular, we plan to identify those types of quantum effects which are most robust against atmospheric disturbances. Our investigations in atmospheric quantum optics will yield the foundations for designing novel methods of free-space quantum communication. This includes aspects ranging from proper data encoding by the sender, secure data transfer via persisting quantum effects, towards optimal detection techniques at the receiver site. We aim at uncovering atmospheric conditions, which may even serve as a resource for quantum communication.

• DFG Programme: Research Grants
• Co-Investigator: Dr. Dmytro Vasylyev