Magnetic Field-Resilient Quantum-Limited Parametric Amplifier

Superconducting parametric amplifiers are crucial components in microwave quantum circuits for enabling quantum-limited signal readout. The best-performing such often based on Josephson junctions, which however sensitive to magnetic fields. Therefore, they require shields and not easily integratable with other systems that operate within fields, as spin-ensemble memories. To tackle this challenge, we develop a kinetic inductance-based amplifier featuring NbN nanobridge instead of provides the desired nonlinearity strong gain up 42 dB. added noise kinetic-inductance (hereby referred NKPA) is calibrated found be 0.59±0.03 quanta phase-preserving amplification, approaching limit 0.5 quanta. Most importantly, show excellent performance preserved an in-plane field 427 mT, maximum available our experiment. This magnetic-field-resilient presents opportunity towards addressing single electron-spin resonance more efficient search axions well Majorana fermions.Received 29 September 2022Accepted 18 January 2023DOI:https://doi.org/10.1103/PRXQuantum.4.010322Published by American Physical Society under terms Creative Commons Attribution 4.0 International license. Further distribution work must maintain attribution author(s) published article's title, journal citation, DOI.Published SocietyPhysics Subject Headings (PhySH)Research AreasKerr effectQuantum engineeringSuperconductorsQuantum InformationCondensed Matter, Materials & Applied Physics