2019/07/31 by J. R. Lane, D. Tan, N. R. Beysengulov +12 · 19 citations
Computer Science · Physics and Astronomy · #Charge qubit #Circuit quantum electrodynamics #Coherence (philosophical gambling strategy) #Condensed matter physics #Dephasing #Microwave #Phase qubit #Physics #Quantum #Quantum Information and Cryptography #Quantum and electron transport phenomena #Quantum computer #Quantum mechanics #Quantum, superfluid, helium dynamics #Qubit #Superconductivity #Superfluid helium-4 #Superfluidity #Transmon #cond-mat.supr-con #quant-ph
paper · pdf · doi:10.1103/physreva.101.012336
published in Physical Review A 101(1) (American Physical Society) · 11 pages, 8 figures
arxiv created 2019/11/18 · openalex publication_date 2020/01/22 · arxiv updated 2020/01/29 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/06
Superfluid helium's low-loss dielectric properties, excellent thermal conductivity, and unique collective excitations make it an attractive candidate to incorporate into superconducting qubit systems. We controllably immerse a three-dimensional superconducting transmon qubit in superfluid 4He and measure the spectroscopic and coherence properties of the system. We find that the cavity, the qubit, and their coupling are all modified by the superfluid, which we analyze within the framework of circuit quantum electrodynamics. At temperatures relevant to quantum computing experiments, the energy relaxation time of the qubit is not significantly changed by the presence of the superfluid, while the pure dephasing time modestly increases, which we attribute to improved thermalization of the microwave environment via the superfluid.