Probing fast quantum circuit refrigeration in the quantum regime

Loading...
Thumbnail Image

Access rights

openAccess
publishedVersion

URL

Journal Title

Journal ISSN

Volume Title

A1 Alkuperäisartikkeli tieteellisessä aikakauslehdessä

Major/Subject

Mcode

Degree programme

Language

en

Pages

6

Series

Physical Review Applied, Volume 23, issue 1, pp. 1-6

Abstract

Recent advancements in circuit quantum electrodynamics have enabled precise manipulation and detection of a single energy quantum in quantum systems. A quantum circuit refrigerator (QCR) is capable of electrically cooling an excited population of quantum systems, such as superconducting resonators and qubits, through photon-assisted tunneling of quasiparticles within a superconductor-insulator-normal-metal junction. In this study, we demonstrate fast QCR in the quantum regime. We perform time-resolved measurement of the QCR-induced cooling of photon number inside a superconducting resonator by harnessing a qubit as a photon detector. From the enhanced photon loss rate of the resonator estimated from the ac Stark shift, the QCR was shown to have a cooling power of approximately 300 aW. Furthermore, even below the single energy quantum, a 100-ns pulse on the QCR can reduce the number of photons inside the resonator below thermal equilibrium. Numerical calculations based on the Lindblad master equation successfully reproduce these experimental results.

Description

Publisher Copyright: © 2025 American Physical Society.

Keywords

Other note

Citation

Nakamura, S, Yoshioka, T, Lemziakov, S, Lvov, D, Mukai, H, Tomonaga, A, Takada, S, Okazaki, Y, Kaneko, N H, Pekola, J & Tsai, J S 2025, 'Probing fast quantum circuit refrigeration in the quantum regime', Physical Review Applied, vol. 23, no. 1, L011003, pp. 1-6. https://doi.org/10.1103/PhysRevApplied.23.L011003