Non-Hermitian State-to-State Analysis of Transport in Aggregates with Multiple Endpoints

Abstract

Efficiency of quantum transport through aggregates with multiple endpoints or traps proves to be an emergent and a highly nonequilibrium phenomenon. We present an exact approach for computing the emergent time-scale and amount of extraction specific to particular traps, leveraging a non-Hermitian generalization of the recently introduced state-to-state transport analysis [Bose and Walters, J. Chem. Theory Comput. 2023, 19, 15, 4828–4836]. This method is able to simultaneously account for the coupling between various sites, the many-body effects brought in by the vibrations and environment held at a nonzero temperature, and the local extraction processes described by non-Hermitian terms in the Hamiltonian. In fact, our non-Hermitian state-to-state analysis goes beyond merely providing an emergent loss time-scale. It can parse the entire dynamics into the constituent internal transport pathways and loss to the environment. We demonstrate this method using examples of exciton transport in a lossy polaritonic cavity. The loss at the cavity and the extraction of the exciton from a terminal molecule provide competing mechanisms that our method helps to unravel, revealing nonintuitive physics. This non-Hermitian state-to-state analysis technique contributes an important link to understanding and elucidating the routes of transport in open quantum systems.

Devansh Sharma

Graduate Student

Amartya Bose

Reader

My primary research interests are in developing physically motivated computational approaches for simulating non-equilibrium quantum dynamics of large systems in a condensed phase.