Submicrometer-scale temperature sensing using quantum coherence of a superconducting qubit

作者：Kosuke Kakuyanagi, Hiraku Toida, L. V. Abdurakhimov, Shiro Saito · 发表于：New Journal of Physics · 年份：2023 · DOI：10.1088/1367-2630/acb379 · 被引用次数：7 · 研究领域：Diamond and Carbon-based Materials Research、Atomic and Subatomic Physics Research、Mechanical and Optical Resonators

Abstract Interest is growing in the development of quantum sensing based on the principles of quantum mechanics, such as discrete energy levels, quantum superposition, and quantum entanglement. Superconducting flux qubits are quantum two-level systems whose energy is sensitive to a magnetic field. Therefore, they can be used as high-sensitivity magnetic field sensors that detect the magnetization of a spin ensemble. Since the magnetization depends on temperature and the magnetic field, the temperature can be determined by measuring the magnetization using the flux qubit. In this study, we demonstrated highly sensitive temperature sensing with high spatial resolution as an application of a magnetic field sensor using the quantum coherence of a superconducting flux qubit. By using a superconducting flux qubit to detect the temperature dependence of the polarization ratio of electron spins in nano-diamond particles, we succeeded in measuring the temperature with a sensitivity of 1.3 µ Kµ Hz − 1 at T = 9.1 mK in the submicrometer range.