2011/03/31 by Baleegh Abdo, Flavius Schackert, Michael Hatridge +2
Computer Science · Engineering · Physics and Astronomy · #Amplifier #Atomic and Subatomic Physics Research #Band-pass filter #Bandwidth (computing) #Center frequency #Condensed matter physics #Engineering #Josephson effect #Microstrip #Microwave #Optics #Optoelectronics #Phase qubit #Physics #Quantum #Quantum Information and Cryptography #Quantum mechanics #Quantum optics and atomic interactions #Qubit #Resonator #Superconductivity #Telecommunications #cond-mat.supr-con #physics.ins-det #quant-ph
paper · pdf · doi:10.1063/1.3653473
published as Appl. Phys. Lett. 99, 162506 (2011) · 9 pages, 4 figures
openalex publication_date 2011/10/17 · arxiv created 2011/10/25 · arxiv updated 2015/05/27 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We report on measurements of a Josephson amplifier (J-amp) suitable for quantum-state qubit readout in the microwave domain. It consists of two microstrip resonators which intersect at a Josephson ring modulator. A maximum gain of about 20 dB, a bandwidth of 9 MHz, and a center-frequency tunability of about 60 MHz with gain in excess of 10 dB have been attained for idler and signal of frequencies 6.4 GHz and 8.1 GHz, in accordance with theory. Maximum input power measurements of the J-amp show a relatively good agreement with theoretical prediction. We discuss how the amplifier characteristics can be improved.