Broadband calibrated scattering parameters characterization of a superconducting quantum interference device amplifierLeonardo Ranzani, Lafe Spietz, José Aumentado
- Applied Physics Letters, January 2013, American Institute of Physics
- DOI: 10.1063/1.4813549
Measurements of the forward gain. reverse transmission and impedance of a DC-SQUID from 1 to 8GHz.
What is it about?
DC-SQUIDs allow the amplification of extremely low-noise signals, with applications to radio-astronomy and superconducting quantum computing. In this work we characterized the scattering parameters of a DC-SQUID (forward/reverse gain and input/output impedance) over several GHz for the first time. In particular we show that the reverse transmission of the DC-SQUID is less than 1 up to 8GHz and we study the impact of the parasitic input/output capacitance on the input impedance.
Why is it important?
These data provide a model of the SQUID that can be used to design new amplifiers with improved bandwidth.