Regensburg 2022 – scientific programme
Parts | Days | Selection | Search | Updates | Downloads | Help
TT: Fachverband Tiefe Temperaturen
TT 7: Fluctuations, Noise, Magnetotransport, and Related Topics
TT 7.3: Talk
Monday, September 5, 2022, 15:30–15:45, H23
Synchronization in Josephson photonics devices with shot noise — •Florian Höhe1, Lukas Danner1, 2, Brecht Donvil1, Ciprian Padurariu1, Björn Kubala1, 2, and Joachim Ankerhold1 — 1ICQ and IQST, Ulm University, Ulm, Germany — 2Institute of Quantum Technologies, German Aerospace Center (DLR), Ulm, Germany
Phase stability is an important characteristic of radiation sources. For quantum sources exploitation and characterization of many quantum properties, such as entanglement and squeezing, may be hampered by phase instability. Josephson photonics devices, where microwave radiation is created by inelastic Cooper pair tunneling across a dc-biased Josephson junction connected in-series with a microwave resonator are particularly vulnerable lacking the reference phase provided by an ac-drive. To counter this issue, sophisticated measurement schemes have been used in [1] to prove entanglement, while in [2] a weak ac-signal was put in to lock phase and frequency of the emission.
The intrinsic shot noise of the Josephson-photonics device inevitably diffuses the oscillators phase and requires an extension of the classical theory [3] describing locking and synchronization to the quantum regime. Here, the shot noise, which is linked to the Full Counting Statistics, induces phase slips. Injection locking and synchronization lead to a strong narrowing of the photon emission statistics.
[1] A. Peugeot et al., Phys. Rev. X 11, 031008 (2021).
[2] M. C. Cassidy et al., Science 355, 939 (2017).
[3] L. Danner et al., Phys. Rev. B 104, 054517 (2021).