Regensburg 2022 – wissenschaftliches Programm
QI 4.5: Poster
Montag, 5. September 2022, 18:00–20:00, P2
Frequency-degenerate Josephson mixer for quantum illumination — •Fabian Kronowetter1,2,3, Florian Fesquet1,2, Maria-Teresa Handschuh1,2, Kedar Honasoge1,2, Yuki Nojiri1,2, Michael Renger1,2, Achim Marx1, Frank Deppe1,2,4, Rudolf Gross1,2,4, and Kirill G. Fedorov1,2 — 1Walther-Meißner-Institut, BAdW, 85748 Garching, Germany — 2Physik-Department, TUM, 85748 Garching, Germany — 3Rohde & Schwarz GmbH, 81671 Munich, Germany — 4Munich Center for Quantum Science and Technology (MCQST), 80799 Munich, Germany
In quantum illumination, the joint measurement of the signal and idler beams enables a quantum advantage in target detection, as compared to the ideal classical radar. This advantage is predicted to exist for the case of weak quantum signals propagating in a bright thermal background, where the latter potentially contains a weakly reflecting target. The joint measurement exploits non-classical correlations between the signal and idler modes. A promising detector concept allowing for a theoretical 3 dB quantum advantage implements this joint measurement by exploiting a frequency-degenerate Josephson mixer (JM). The circuit of this JM consists of two 180∘ hybrid ring beam splitters and two flux-driven Josephson parametric amplifiers. We present the first successful operation of the frequency-degenerate JM with Gaussian states and, thus, demonstrate an important milestone for the realization of the microwave quantum radar.