Regensburg 2019 – scientific programme

Parts | Days | Selection | Search | Updates | Downloads | Help

TT: Fachverband Tiefe Temperaturen

TT 67: Cryogenic Particle Detectors and Other Superconducting Electronics

TT 67.4: Talk

Friday, April 5, 2019, 10:15–10:30, H4

Saturation power measurement for a non-degenerate parametric amplifier based on a dispersion engineered SQUID array. — •Ivan Takmakov^1,2, Patrick Winkel¹, Farshad Foroughi^3,4, Luca Planat^3,4, Javier Puertas Martinez^3,4, Wolfgang Wernsdorfer^1,2, Alexey Ustinov^1,2,5, Ioan Pop^1,2, and Nicolas Roch^3,4 — ¹Physikalisches Institut, Karlsruhe Institute of Technology, Germany — ²Institute of Nanotechnology, Karlsruhe Institute of Technology, Germany — ³Universite Grenoble Alpes, Institut NEEL, France — ⁴CNRS, Institut NEEL, France — ⁵Russian Quantum Center, National University of Science and Technology MISIS, Russia

Saturation power is one of the most important characteristics of an amplifier. For a Josephson Parametric Amplifier (JPA) its accurate measurement imposes a challenge. A JPA is typically operated at 20mK and the attenuation of coaxial cables changes when they are cooled down. Thus a calibration is required to know the power of a microwave signal at the input of a JPA.

We present measurements of saturation power of a Dimer Josephson Junction Array Amplifier (DJJAA). The amplifier is based on a dispersion engineered SQUID array. In order to measure the amplifier's saturation power, in front of a DJJAA we connect a transmon qubit coupled to a transmission line. The transmission through this chip depends on the power of a signal. Using this dependence we can measure the signal power at the qubit sample and thus perform a calibration for the saturation power measurements.