Regensburg 2019 – wissenschaftliches Programm
TT 10.7: Vortrag
Montag, 1. April 2019, 18:00–18:15, H2
Generating Pairs of Entangled Microwave Photons by Josephson-Photonics Devices — •Simon Dambach1, Ambroise Peugeot2, Juha Leppäkangas3, Björn Kubala1, Marc Westig2, Yuri Mukharsky2, Carles Altimiras2, Denis Vion2, Daniel Esteve2, Fabien Portier2, and Joachim Ankerhold1 — 1Institut für komplexe Quantensysteme, Universität Ulm, Germany — 2SPEC (UMR 3680 CEA-CNRS), CEA Paris-Saclay, France — 3Physikalisches Institut, Karlsruher Institut für Technologie, Germany
The realization of bright and efficient sources for entangled microwave photons is considered of paramount importance for many future applications of quantum technology. Josephson-photonics devices are very promising candidates for this task since they allow one to create a broad range of different entangled states in a surprisingly simple way . In these devices, Cooper-pair tunneling across a dc-voltage–biased Josephson junction simultaneously creates photons in several series-connected microwave cavities. Steady states with multifaceted entanglement properties are reached naturally due to the interplay of these multiphoton creation processes and subsequent individual photon leakage from the cavities. Sophisticated pulse shaping as required in conventional circuit-QED architectures is thus not necessary here. In this talk, we present a theoretical study of the bipartite entanglement in both the cavity modes and the output transmission lines. Analytical results for weak driving, complemented by numerical calculations for the full nonlinear case, show good agreement with experimental data.
 S. Dambach et al., New J. Phys. 19, 023027 (2017).