Cuzminschi Marina, Zubarev Alexei, Isar Aurelian
Department of Theoretical Physics, National Institute for Physics and Nuclear Engineering, 077125, Magurele-Bucharest, Romania.
Faculty of Physics, University of Bucharest, 077125, Magurele-Bucharest, Romania.
Sci Rep. 2021 Dec 20;11(1):24286. doi: 10.1038/s41598-021-03752-4.
We study a Szilard engine based on a Gaussian state of a system consisting of two bosonic modes placed in a noisy channel. As the initial state of the system is taken an entangled squeezed thermal state, and the quantum work is extracted by performing a measurement on one of the two modes. We use the Markovian Kossakowski-Lindblad master equation for describing the time evolution of the open system and the quantum work definition based on the second order Rényi entropy to simulate the engine. We also study the information-work efficiency of the Szilard engine as a function of the system parameters. The efficiency is defined as the ratio of the extractable work averaged over the measurement angle and the erasure work, which is proportional to the information stored in the system. We show that the extractable quantum work increases with the temperature of the reservoir and the squeezing between the modes, average numbers of thermal photons and frequencies of the modes. The work increases also with the strength of the measurement, attaining the maximal values in the case of a heterodyne detection. The extractable work is decreasing by increasing the squeezing parameter of the noisy channel and it oscillates with the phase of the squeezed thermal reservoir. The efficiency mostly has a similar behavior with the extractable quantum work evolution. However information-work efficiency decreases with temperature, while the quantity of the extractable work increases.
我们研究了一种基于由置于噪声信道中的两个玻色子模式组成的系统的高斯态的西拉德引擎。系统的初始态取为纠缠压缩热态，通过对两个模式之一进行测量来提取量子功。我们使用马尔可夫型的科萨克夫斯基 - 林德布拉德主方程来描述开放系统的时间演化，并基于二阶雷尼熵的量子功定义来模拟该引擎。我们还研究了西拉德引擎的信息 - 功效率作为系统参数的函数。效率定义为测量角度上平均可提取功与擦除功的比值，擦除功与系统中存储的信息成正比。我们表明，可提取的量子功随着热库温度、模式间的压缩、热光子的平均数以及模式的频率而增加。功也随着测量强度增加，在外差检测的情况下达到最大值。通过增加噪声信道的压缩参数，可提取功会减小，并且它会随着压缩热库的相位振荡。效率大多与可提取量子功的演化具有相似的行为。然而，信息 - 功效率随温度降低，而可提取功的量增加。
