Strong environmental coupling in a Josephson parametric amplifier

Journal Article · Mon Jun 30 00:00:00 EDT 2014 · Applied Physics Letters

DOI:https://doi.org/10.1063/1.4886408· OSTI ID:22303915

Mutus, J. Y.; White, T. C.; Barends, R.; Chen, Yu; Chen, Z.; Chiaro, B.; Dunsworth, A.; Jeffrey, E.; Kelly, J.; Neill, C.; O'Malley, P. J. J.; Roushan, P.; Sank, D.; Vainsencher, A.; Wenner, J.; Cleland, A. N.; Megrant, A. ^[1]; Sundqvist, K. M. ^[2]

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1. Department of Physics, University of California, Santa Barbara, California 93106-9530 (United States)
2. Department of Electrical and Computer Engineering, Texas A and M University, College Station, Texas 77843 (United States)

We present a lumped-element Josephson parametric amplifier designed to operate with strong coupling to the environment. In this regime, we observe broadband frequency dependent amplification with multi-peaked gain profiles. We account for this behavior using the “pumpistor” model which allows for frequency dependent variation of the external impedance. Using this understanding, we demonstrate control over the complexity of gain profiles through added variation in the environment impedance at a given frequency. With strong coupling to a suitable external impedance, we observe a significant increase in dynamic range, and large amplification bandwidth up to 700 MHz giving near quantum-limited performance.

• OSTI ID: 22303915
• Journal Information: Applied Physics Letters, Vol. 104, Issue 26; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); ISSN 0003-6951
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
CONTROL
COUPLING
FREQUENCY DEPENDENCE
GAIN
IMPEDANCE
MHZ RANGE
PARAMETRIC AMPLIFIERS
STRONG-COUPLING MODEL