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A near-quantum-limited Josephson traveling-wave parametric amplifier
C Macklin1, K O'Brien2, D Hover3
1Quantum Nanoelectronics Laboratory, University of California, Berkeley, Berkeley, CA 94720, USA. Computational Research Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA. chris.macklin@berkeley.edu.
Science (New York, N.Y.)
|September 5, 2015
Summary
We developed a new Josephson junction superconducting amplifier for detecting faint microwave signals. This traveling wave device offers high gain and broad bandwidth, crucial for quantum information processing and metrology.
Area of Science:
- Quantum Optics
- Superconducting Devices
- Microwave Engineering
Background:
- Detecting single-photon level microwave signals is critical for quantum information science but technically challenging.
- Existing superconducting amplifiers often lack the required gain, bandwidth, or dynamic range for advanced applications like reading out multiple qubits.
Purpose of the Study:
- To introduce a novel superconducting amplifier architecture for enhanced detection of low-energy microwave signals.
- To achieve high gain, broad bandwidth, and sufficient dynamic range for reading out numerous superconducting qubits.
Main Methods:
- Development of a traveling-wave superconducting amplifier utilizing a Josephson junction transmission line.
- Implementation of a subwavelength resonant phase-matching technique to engineer unique nonlinear microwave device dispersion relations.
- Benchmarking the amplifier's performance using weak measurements.
Main Results:
- The Josephson amplifier demonstrates robust high gain over a multi-gigahertz bandwidth.
- The device exhibits sufficient dynamic range to facilitate the readout of up to 20 superconducting qubits.
- A high quantum efficiency of 75% (70% including subsequent amplifier noise) was achieved.
Conclusions:
- The developed traveling-wave Josephson amplifier offers a significant advancement over existing technologies.
- Its flexible design and high performance make it broadly applicable to microwave metrology and quantum optics.
- This technology is poised to benefit the advancement of quantum computing and sensitive signal detection.
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