title: Nonequilibrium Energy Transfer at Nanoscale: A Unified Theory from Weak to Strong Coupling.
abstract: Unraveling the microscopic mechanism of quantum energy transfer across two-level systems provides crucial insights to the optimal design and potential applications of low-dimensional nanodevices. Here, we study the non-equilibrium spin-boson model as a minimal prototype and develop a fluctuation-decoupled quantum master equation approach that is valid ranging from the weak to the strong system-bath coupling regime. The exact expression of energy flux is analytically established, which dissects the energy transfer as multiple boson processes with even and odd parity. Our analysis provides a unified interpretation of several observations, including coherence-enhanced heat flux and negative differential thermal conductance. The results will have broad implications for the fine control of energy transfer in nano-structural devices.
authors.affiliation: 1] Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA [2] Singapore-MIT Alliance for Research and Technology, 1 CREATE Way, Singapore 138602, Singapore [3] Department of Physics, Hangzhou Dianzi University, Hangzhou, Zhejiang 310018, China.
authors.forename: Chen
authors.initials: C
authors.lastname: Wang
authors.affiliation: 1] Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA [2] Center for Phononics and Thermal Energy Science, School of Physics Science and Engineering, Tongji University, 200092 Shanghai, P. R. China.
authors.forename: Jie
authors.initials: J
authors.lastname: Ren
authors.affiliation: 1] Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA [2] Singapore-MIT Alliance for Research and Technology, 1 CREATE Way, Singapore 138602, Singapore.
authors.forename: Jianshu
authors.initials: J
authors.lastname: Cao