Effective Mass Path Integral Simulations of Quasiparticles in Condensed Phases

TL;DR

This paper presents a novel computational approach combining effective mass theory with path integral methods to simulate quasiparticles in condensed phases, capturing their behavior in complex environments and nanostructures.

Contribution

The authors develop an effective mass path integral simulation framework that incorporates anisotropic band structures for modeling quasiparticles in condensed matter.

Findings

Successfully modeled an exciton in solid potassium chloride.

Simulated electron trapping by sulfur vacancies in monolayer molybdenum disulfide.

Demonstrated the method's ability to handle quantum confinement effects.

Abstract

The quantum many-body problem in condensed phases is often simplified using a quasiparticle description, such as effective mass theory for electron motion in a periodic solid. These approaches are often the basis for understanding many fundamental condensed phase processes, including the molecular mechanisms underlying solar energy harvesting and photocatalysis. Despite the importance of these effective particles, there is still a need for computational methods that can explore their behavior on chemically relevant length and time scales. This is especially true when the interactions between the particles and their environment are important. We introduce an approach for studying quasiparticles in condensed phases by combining effective mass theory with the path integral treatment of quantum particles. This framework incorporates the generally anisotropic electronic band structure of materials into path integral simulation schemes to enable modeling of quasiparticles in quantum confinement, for example. We demonstrate the utility of effective mass path integral simulations by modeling an exciton in solid potassium chloride and electron trapping by a sulfur vacancy in monolayer molybdenum disulfide.