2025-01-09 チャルマース工科大学
＜関連情報＞
- https://news.cision.com/chalmers/r/record-cold-quantum-refrigerator-paves-way-for-reliable-quantum-computers,c4080641
- https://www.nature.com/articles/s41567-024-02708-5
熱駆動量子冷凍機が超伝導量子ビットを自律的にリセットする Thermally driven quantum refrigerator autonomously resets a superconducting qubit
Mohammed Ali Aamir,Paul Jamet Suria,José Antonio Marín Guzmán,Claudia Castillo-Moreno,Jeffrey M. Epstein,Nicole Yunger Halpern & Simone Gasparinetti
Nature Physics Published:09 January 2025
DOI:https://doi.org/10.1038/s41567-024-02708-5
Abstract
Although classical thermal machines power industries and modern living, quantum thermal engines have yet to prove their utility. Here, we demonstrate a useful quantum absorption refrigerator formed from superconducting circuits. We use it to cool a transmon qubit to a temperature lower than that achievable with any one available bath, thereby resetting the qubit to an initial state suitable for quantum computing. The process is driven by a thermal gradient and is autonomous, requiring no external feedback. The refrigerator exploits an engineered three-body interaction between the target qubit and two auxiliary qudits. Each auxiliary qudit is coupled to a physical heat bath, realized with a microwave waveguide populated with synthesized quasithermal radiation. If the target qubit is initially fully excited, its effective temperature reaches a steady-state level of approximately 22 mK, lower than what can be achieved by existing state-of-the-art reset protocols. Our results demonstrate that superconducting circuits with propagating thermal fields can be used to experimentally explore quantum thermodynamics and apply it to quantum information-processing tasks.
