Superconducting Travelling-Wave Amplifier Isolator: Up to 20 dB Gain, 30 dB Isolation, Over 500 MHz Bandwidth
Research published in Nature Electronics on 14 November 2025 reports a Josephson-junction-based travelling-wave parametric amplifier isolator that combines amplification and isolation in a single device.
The device can provide gain of up to 20 dB and reverse isolation of up to 30 dB over a static 3-dB bandwidth greater than 500 MHz, while maintaining near-quantum-limited added noise.
The researchers said such devices could potentially eliminate the need for separate isolators in quantum measurement systems, reduce hardware overhead in superconducting quantum computers, and be integrated on chip with superconducting qubits.
Source: Nature Electronics
Published by GSM · USA (original Chinese edition)
Photo: 约瑟夫森行波参量放大器（J-TWPA）器件图。照片：OJB Quantum，CC BY 4.0，经 Wikimedia Commons / Josephson travelling-wave parametric amplifier. Photo: OJB Quantum, CC BY 4.0, via Wikimedia Commons
