Amplifying Quantum Signals with Kinetic Inductance Superconducting Microstrips

  Samuel Goldstein  ,  Naftali Kirsh [1]  ,  Elisha Svetitsky [1]  ,  Yuval Zamir [1]  ,  Ori Hachmo [1]  ,  Shimon Eliav [2]  ,  Nadav Katz [1]  
[1] The Racah Institute of Physics, The Hebrew University of Jerusalem
[2] The Harvey M. Krueger Family Center for Nanoscience and Nanotechnology, The Hebrew University of Jerusalem

Superconducting quantum circuits are operated at very low powers (<-130 dBm), necessitating cryogenic low-noise, wide-band amplifiers for readout compatible with room temperature electronics. We develop a MIcrostrip Kinetic Inductance Travelling wave Amplifier (MIKITA), exploiting the non-linear kinetic inductance of tungsten-silicide for wave-mixing of the signal and a pump. Unlike other implementations, our approach allows nearly perfect impedance matching, limiting the noise in the amplifier. Our device is fabricated with standard lithography, and amplifies by 15 dB over a 1 GHz bandwidth, with a dynamic range spanning more than four orders of magnitude.