Berlin 2015 – wissenschaftliches Programm
TT 21.44: Poster
Montag, 16. März 2015, 15:00–18:00, Poster B
Characterization of Josephson parametric amplifiers — •Stefan Pogorzalek1,2,3, Kirill Fedorov1,2,3, Ling Zhong1,2,3, Martin Bitzenbichler1,2,3, Max Haeberlein1,2,3, Manuel J. Schwarz1,2,3, Peter Eder1,2,3, Jan Goetz1,2,3, Friedrich Wulschner1,2,3, Edwar Xie1,2,3, Alexander Baust1,2,3, Achim Marx1,2,3, Edwin P. Menzel1,2,3, Frank Deppe1,2,3, and Rudolf Gross1,2,3 — 1Walther-Meißner-Institut, Bayerische Akademie der Wissenschaften, 85748 Garching, Germany — 2Physik-Department, TU München, 85748 Garching, Germany — 3Nanosystems Initiative Munich (NIM), 80799 München, Germany
Propagating quantum microwaves are a promising building block for quantum communication. In particular, such itinerant quantum microwaves can be generated in the form of squeezed photon states using Josephson parametric amplifiers (JPA). A thorough experimental characterization of JPAs is therefore an essential prerequisite for further experiments towards quantum communication. For implementing JPAs we employ an established λ /4 bi-coplanar microwave resonator design where a dc-SQUID is biased by an external flux to tune the resonant frequency. An inductively coupled antenna acts as a pump for the JPA. We characterize several JPAs and evaluate the data within standard Josephson junction theory and the input-output formalism. In particular, we investigate hysteretic and bifurcation behavior of the JPAs in addition to usual non-degenerate JPA gain measurements.
This work is supported by the DFG via SFB 631 and the EU projects CCQED and PROMISCE.