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arXiv · 2302.13930

High-kinetic inductance NbN films for high-quality compact superconducting resonators

Simone Frasca·Ivo Nikolaev Arabadzhiev·Sebastien Yves Bros de Puechredon·Fabian Oppliger·Vincent Jouanny·Roberto Musio·Marco Scigliuzzo·Fabrizio Minganti·Pasquale Scarlino·Edoardo Charbon
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Abstract

Niobium nitride (NbN) is a particularly promising material for quantum technology applications, as entails the degree of reproducibility necessary for large-scale of superconducting circuits. We demonstrate that resonators based on NbN thin films present a one-photon internal quality factor above 10$^5$ maintaining a high impedance (larger than 2k$\Omega$), with a footprint of approximately 50x100 $\mu$m$^2$ and a self-Kerr nonlinearity of few tenths of Hz. These quality factors, mostly limited by losses induced by the coupling to two-level systems, have been maintained for kinetic inductances ranging from tenths to hundreds of pH/square. We also demonstrate minimal variations in the performance of the resonators during multiple cooldowns over more than nine months. Our work proves the versatility of niobium nitride high-kinetic inductance resonators, opening perspectives towards the fabrication of compact, high-impedance and high-quality multimode circuits, with sizable interactions.

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Simone Frasca, Ivo Nikolaev Arabadzhiev, Sebastien Yves Bros de Puechredon, Fabian Oppliger, Vincent Jouanny, Roberto Musio, Marco Scigliuzzo, Fabrizio Minganti, Pasquale Scarlino, Edoardo Charbon. 2023-02-27. High-kinetic inductance NbN films for high-quality compact superconducting resonators. https://doi.org/10.1103/physrevapplied.20.044021

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