Improving the Time Stability of Superconducting Planar Resonators

Abstract

Quantum computers are close to become a practical technology. Solid-state implementations based, for example, on superconducting devices strongly rely on the quality of the constituent materials. In this work, we fabricate and characterize superconducting planar resonators in the microwave range, made from aluminum films on silicon substrates. We study two samples, one of which is unprocessed and the other cleaned with a hydrofluoric acid bath and by heating at $880^{\circ }$C in high vacuum. We verify the efficacy of the cleaning treatment by means of scanning transmission electron microscope imaging of samples' cross sections. From 3 h-long resonator measurements at $\approx 10$ mK and with $\approx 10$ photonic excitations, we estimate the frequency flicker noise level using the Allan deviation and find an approximately tenfold noise reduction between the two samples; the cleaned sample shows a flicker noise power coefficient for the fractional frequency of $\approx 0.23\times 10^{-15}$. Our preliminary results follow the generalized tunneling model for two-level state defects in amorphous dielectric materials and show that suitable cleaning treatments can help the operation of superconducting quantum computers.

arXiv comment13 pages, 5 figures, 2 tables; submitted

References in corpus (14)

• Quantum Computing
• Surface codes: Towards practical large-scale quantum computation
• Quantum algorithms: an overview
• Planar Superconducting Resonators with Internal Quality Factors above One Million
• Fluctuations of Energy-Relaxation Times in Superconducting Qubits
• Correlating decoherence in transmon qubits: Low frequency noise by single fluctuators
• Analysis and mitigation of interface losses in trenched superconducting coplanar waveguide resonators
• A semi-empirical model for two-level system noise in superconducting microresonators
• Interacting two-level defects as sources of fluctuating high-frequency noise in superconducting circuits
• Suppression of 1/f noise in solid state quantum devices by surface spin desorption
• Substrate surface engineering for high-quality silicon/aluminum superconducting resonators
• The Quantum Socket: Three-Dimensional Wiring for Extensible Quantum Computing
• Pound-locking for characterization of superconducting microresonators
• Mitigating coherent leakage of superconducting qubits in a large-scale quantum socket

Cited by in corpus (2)

• Fluctuation Spectroscopy of Two-Level Systems in Superconducting Resonators
• Resonant Coupling Parameter Estimation with Superconducting Qubits