A long-lived capacitively shunted flux qubit embedded in a 3D cavity

Abstract

We report the experimental realization of a 3D capacitively-shunt superconducting flux qubit with long coherence times. At the optimal flux bias point, the qubit demonstrates energy relaxation times in the 60-90 $\mu$s range, and Hahn-echo coherence time of about 80 $\mu$s which can be further improved by dynamical decoupling. Qubit energy relaxation can be attributed to quasiparticle tunneling, while qubit dephasing is caused by flux noise away from the optimal point. Our results show that 3D c-shunt flux qubits demonstrate improved performance over other types of flux qubits which is advantageous for applications such as quantum magnetometry and spin sensing.

main text (4 pages) + supplementary materials (6 pages), submitted to APL

References in corpus (11)

• Charge insensitive qubit design derived from the Cooper pair box
• Dynamical decoupling and noise spectroscopy with a superconducting flux qubit
• Superconducting qubit in waveguide cavity with coherence time approaching 0.1ms
• Decoherence of flux qubits due to 1/f flux noise
• Decoherence benchmarking of superconducting qubits
• Low-decoherence flux qubit
• Dephasing of a superconducting flux qubit
• Quasiparticle relaxation of superconducting qubits in the presence of flux
• Improved Superconducting Qubit Readout by Qubit-Induced Nonlinearities
• Response of the Strongly-Driven Jaynes-Cummings Oscillator
• Ultrasensitive magnetic field detection using a single artificial atom

Cited by in corpus (3)

• Photon-Dressed Bloch-Siegert Shift in an Ultrastrongly Coupled Circuit Quantum Electrodynamical System
• Driven-state relaxation of a coupled qubit-defect system in spin-locking measurements
• Control of transition frequency of a superconducting flux qubit by longitudinal coupling to the photon number degree of freedom in a resonator