Reduced Density-Matrix Approach to Strong Matter-Photon Interaction
Year: 2018
Type: report
Abstract: In this work, we present a first-principles approach to electronic many-body systems strongly coupled to cavity modes in terms of matter-photon reduced density matrices. The theory is fundamentally non-perturbative and thus captures not only the effects of correlated electronic systems but accounts also for strong interactions between matter and photon egrees of freedom. We do so by introducing a higher-dimensional auxiliary system that maps the coupled fermion-boson system to a purely fermionic problem as proposed recently in the context of density-functional theory (arXiv:1812.00388(N)). This reformulation allows us to overcome many fundamental challenges of density-matrix theory in the context of coupled fermion-boson systems and we can employ conventional reduced density-matrix functional theory developed for purely fermionic systems. We provide results for model systems in real space and show that simple density-matrix approximations are accurate from the weak to the deep-strong coupling regime.
Source: MPG.PuRe (Max Planck Society)
Authors: Buchholz, F., Theophilou, I., Nielsen, S., Ruggenthaler, M., Rubio, A.
Language: English
Subfield: Atomic and Molecular Physics, and Optics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: green
Funder: H2020 European Research Council
Award: G744112565
OpenAlex ID: W3104872172