Combining density functional theory with macroscopic QED for quantum light-matter interactions in 2D materials

Abstract

A quantitative and predictive theory of quantum light-matter interactions in ultra thin materials involves several fundamental challenges. Any realistic model must simultaneously account for the ultra-confined plasmonic modes and their quantization in the presence of losses, while describing the electronic states from first principles. Herein we develop such a framework by combining density functional theory (DFT) with macroscopic quantum electrodynamics, which we use to show Purcell enhancements reaching 107 for intersubband transitions in few-layer transition metal dichalcogenides sandwiched between graphene and a perfect conductor. The general validity of our methodology allows us to put several common approximation paradigms to quantitative test, namely the dipole-approximation, the use of 1D quantum well model wave functions, and the Fermi’s Golden rule. The analysis shows that the choice of wave functions is of particular importance. Our work lays the foundation for practical ab initio-based quantum treatments of light-matter interactions in realistic nanostructured materials.

Quantum Optical Effective-Medium Theory for Layered Metamaterials at Any Angle of Incidence

“…[ 79 ] and has broad applicability. For example, it could be used to generalize multi-emitter nanophotonics theories [ 80 , 81 , 82 ] to situations where background media can have loss but also gain. Here, instead, we will use it to derive quantum effective-medium theories for metamaterials.…”

Tunable Nonlinearity and Efficient Harmonic Generation from a Strongly Coupled Light–Matter System

“…For an accurate study, it is important to employ first-principles approaches that can describe the complex interaction when light and matter strongly interact. Such first-principles methods have been developed within the framework of nonrelativistic quantum electrodynamics. − Among these methods, quantum electrodynamical density functional theory (QEDFT) is a valuable approach for describing ground- and excited-state properties of complex matter systems coupled to photons − and suitable to investigate nonlinear optical processes of strongly coupled light–matter systems.…”

Entangled biphoton enhanced double quantum coherence signal as a probe for cavity polariton correlations in presence of phonon induced dephasing

“…These methods have offered several different flavors of treating the matter and the cavity modes. We have, namely, quantum electrodynamics based hybrid (density) functional formulation [79][80][81][82], cluster-expansion [21], potential-energy surface-based dynamical calculations combined with the trajectory-based propagation for the cavity quadrature modes [83,84], path integral based unified framework for nuclear modes and the idealized cavity modes [85][86][87], first-principles simulations [88][89][90][91][92]. Incorporating these methods to describe the phenomenology described in this article will require a qualified description of exciton formation, a description of exciton-exciton scattering in the presence of a dielectric environment, and nuclear propagation.…”