Mannila E T, Maisi V F, Pekola J P
QTF Centre of Excellence, Department of Applied Physics, Aalto University, FI-00076 Aalto, Finland.
Physics Department and NanoLund, Lund University, Box 118, 22100 Lund, Sweden.
Phys Rev Lett. 2021 Oct 1;127(14):147001. doi: 10.1103/PhysRevLett.127.147001.
We propose and experimentally demonstrate a self-calibrating detector of Cooper pair depairing in a superconductor based on a mesoscopic superconducting island coupled to normal metal leads. On average, exactly one electron passes through the device per broken Cooper pair, independent of the absorber volume, device, or material parameters. The device operation is explained by a simple analytical model and verified with numerical simulations in quantitative agreement with experiment. In a proof-of-concept experiment, we use such a detector to measure the high-frequency phonons generated by another, electrically decoupled superconducting island, with a measurable signal resulting from less than 10 fW of dissipated power.
我们提出并通过实验证明了一种基于耦合到正常金属引线的介观超导岛的超导体中库珀对解配对的自校准探测器。平均而言，每一个破裂的库珀对恰好有一个电子通过该器件，这与吸收体体积、器件或材料参数无关。该器件的运行由一个简单的分析模型解释，并通过与实验定量一致的数值模拟进行了验证。在一个概念验证实验中，我们使用这样一个探测器来测量由另一个电去耦超导岛产生的高频声子，产生可测量信号所需的耗散功率小于10飞瓦。
