Elementary Excitations in Monolayer Defect Lattices

Expanding the repertoire of two dimensional materials is of fundamental importance for the viability of optoelectronic and plasmonic properties beyond those achievable by canonical low dimensional materials such as graphene. Herein, we explore the landscape of carbon substitutional defects in hexagonal boron nitride and explicate their electronic, phononic, and plasmonic properties through the use of Density Functional Theory. We report the structural stability of our candidate materials, their band structures as a function of electronic doping, as well as their TM polarized plasmonic dispersions, confinements, and losses. We show that a simple analytical model explains doping induced changes in the spectra of optical excitations in our materials to a high level of accuracy. Our work also indicates that this new class of plasmonic materials allows for tunable plasmonic excitations in the infrared with confinements that exceed those of graphene plasmons by more than an order of magnitude and which maintain comparatively low losses. We envision that our study of this class of materials will open the door for studies of artificially designed two dimensional materials beyond the currently available landscape.