Environmental engineering for quantum transport

　The quick development of quantum technology has shortened the scale of measurements, approaching the correlation time of the environmental variables surrounding the system of interest. With the development, new research avenues have been opened for environmental engineering. We study the possibility of improving the efficiency of quantum transport[1] and work extraction of a quantum heat engine[2] by utilizing characteristic features of the environment, such as spatial-time correlation and spectral density. We also show a formulation to describe the reduced dynamics of quantum interacting systems that enables us to extend the applicabilities on the parameter setting as Bohr frequencies of subsystems, to preserve positivity in the short time region, and to describe the dynamics approaching the thermodynamically consistent stationary state, even if only the terminal site interacts with its environment[3]. References: [1]C. Uchiyama, W. J. Munro, and K. Nemoto, npj Quantum Information 4,33 (2018). [2]Y. Shirai, K. Hashimoto, R. Tezuka, C. Uchiyama, and N. Hatano, Phys. Rev. Res. 3, 023078 (2021). [3]C. Uchiyama, Phys. Rev. A 108, 042212 (2023).