arXiv subjects

Hao-Yang Qi

Publications and source records attributed to Hao-Yang Qi.

2 recordsLinked to original sources

arXiv2026

Local thermal probe in a one-dimensional chain: An efficient dissipaton-based approach

We study a system consisting of an infinite one-dimensional molecular chain and a locally coupled probe. Starting from the Hamiltonian of the chain-probe composite and the corresponding spectral densities, we evaluate the heat current between the probe and the chain. For this purpose, we develop a dissipaton-based quantum approach that is fully nonperturbative and non-Markovian. The dissipaton algebra yields a set of hierarchically coupled equations of motion for the dissipaton moments, with cross-tier connections in an iterative manner if higher-order chain-probe interactions are included. Numerical results demonstrate the effects of temperature, frequency, onsite energy modification and higher-order couplings on heat transport. This work provides a general framework for thermal transport and other properties in locally probed systems and can be straightforwardly extended to higher-dimensional materials and electronic transport problems with strong many-body effects.

physics.chem-ph↗

arXiv2024

Extended system-bath entanglement theorem for multiple bosonic or fermionic environments

The system-bath entanglement theorem (SBET) was established in terms of linear response functions [J. Chem. Phys. 152, 034102 (2020)] and generalized to correlation functions [arXiv: 2312.13618 (2023)] in our previous works. This theorem connects the entangled system-bath properties to the local system and bare bath ones. In this work, firstly we extend the SBET to field-dressed conditions with multiple bosonic Gaussian environments at different temperatures. Not only the system but also environments are considered to be of optical polarizability, as in reality. With the aid of the extended SBET developed here, for the evaluation of the nonlinear spectroscopy such as the pump-probe, the entangled system-bath contributions can be obtained upon reduced system evolutions via certain quantum dissipative methods. The extended SBET in the field-free condition and its counterpart in the classical limit is also presented. The SBET for fermionic environments is elaborated within the transport scenarios for completeness.

quant-ph↗