Routes of Transport in the Path Integral Lindblad Dynamics through State-to-State Analysis

TL;DR

This paper extends the state-to-state analysis method to Lindblad dynamics, enabling detailed study of transport routes in open quantum systems with diverse dissipative and pumping processes, demonstrated on excitonic aggregates.

Contribution

The authors develop a Lindblad-based state-to-state analysis framework for open quantum systems, broadening the applicability beyond non-Hermitian models to include general dissipative and pumping effects.

Findings

The method elucidates transport routes in systems coupled to thermal baths with Lindblad operators.

It demonstrates the establishment of steady-state excitonic currents in molecular aggregates.

Provides a first-principles approach to quantifying excitonic transport under complex dissipative conditions.

Abstract

Analyzing routes of transport for open quantum systems with non-equilibrium initial conditions is extremely challenging. The state-to-state approach [A. Bose, and P.L. Walters, J. Chem. Theory Comput. 2023, 19, 15, 4828-4836] has proven to be a useful method for understanding transport mechanisms in quantum systems interacting with dissipative thermal baths, and has been recently extended to non-Hermitian systems to account for empirical loss. These non-Hermitian descriptions are, however, not capable of describing empirical processes of more general nature, including but not limited to a variety of pumping processes. We extend the state-to-state analysis to account for Lindbladian descriptions of generic dissipative, pumping and decohering processes acting on a system which is exchanging energy with a thermal bath. This Lindblad state-to-state method can elucidate routes of transport in systems coupled to a bath and additionally acted upon by Lindblad jump operators. The method is demonstrated using examples of excitonic aggregates subject to incoherent pumping and draining processes. Using this new state-to-state formalism, we demonstrate the establishment of steady-state excitonic currents across molecular aggregates, yielding a different first-principles approach to quantifying the same.