Bhandari Bibek, Czupryniak Robert, Erdman Paolo Andrea, Jordan Andrew N
Institute for Quantum Studies, Chapman University, Orange, CA 92866, USA.
Department of Physics and Astronomy, University of Rochester, Rochester, NY 14627, USA.
Entropy (Basel). 2023 Jan 20;25(2):204. doi: 10.3390/e25020204.
We investigated coupled-qubit-based thermal machines powered by quantum measurements and feedback. We considered two different versions of the machine: (1) a quantum Maxwell's demon, where the coupled-qubit system is connected to a detachable single shared bath, and (2) a measurement-assisted refrigerator, where the coupled-qubit system is in contact with a hot and cold bath. In the quantum Maxwell's demon case, we discuss both discrete and continuous measurements. We found that the power output from a single qubit-based device can be improved by coupling it to the second qubit. We further found that the simultaneous measurement of both qubits can produce higher net heat extraction compared to two setups operated in parallel where only single-qubit measurements are performed. In the refrigerator case, we used continuous measurement and unitary operations to power the coupled-qubit-based refrigerator. We found that the cooling power of a refrigerator operated with swap operations can be enhanced by performing suitable measurements.
我们研究了由量子测量和反馈驱动的基于耦合量子比特的热机。我们考虑了该热机的两种不同版本：（1）量子麦克斯韦妖，其中耦合量子比特系统连接到一个可拆卸的单一共享热库；（2）测量辅助制冷机，其中耦合量子比特系统与一个热库和一个冷库接触。在量子麦克斯韦妖的情况下，我们讨论了离散测量和连续测量。我们发现，通过将基于单个量子比特的设备与第二个量子比特耦合，可以提高其功率输出。我们还发现，与仅执行单量子比特测量的两个并行运行的设置相比，同时测量两个量子比特可以产生更高的净热提取。在制冷机的情况下，我们使用连续测量和幺正操作来驱动基于耦合量子比特的制冷机。我们发现，通过执行适当的测量，可以提高采用交换操作运行的制冷机的冷却功率。
