Doctoral student Victor Gabriel Morele Duarte has published an article (https://doi.org/10.1103/PhysRevB.111.075411) in the prestigious journal Physical Review B, bringing an innovative contribution to the field of polaritonics. The work was co-authored with his advisor, Prof. André Chaves from PG-FIS, his co-advisor Prof. Nuno Peres from the University of Minho in Portugal, and his collaborators Pedro Ninhos, Prof. C. Tserkezis, and Prof. N. Asger Mortensen from the University of Southern Denmark.
Exciton-polaritons, quantum hybrids of light and matter, are at the forefront of research on new optical technologies, ranging from ultra-sensitive sensors to groundbreaking quantum memories. In a significant breakthrough, researchers have demonstrated that inserting electrically biased bilayer graphene inside an optical cavity can create a highly tunable platform for strong light-matter interactions.
The study innovatively explores how the introduction of this two-dimensional material enables precise control over the energy-momentum dispersion relations of polaritons and the strength of light-matter coupling (Rabi splitting). Using two interconnected approaches—one semiclassical and the other fully quantum—the authors analyze the polariton dispersion, Hopfield coefficients, and the characteristic spectral splitting of strong coupling. One of the study's highlights is the inclusion of materials with near-zero permittivity ("epsilon-near-zero"), which further enhance exciton-photon interaction, expanding the practical application possibilities of this technology.
The flexibility of this platform allows for unprecedented tuning of the system's optical response, paving the way for highly efficient and reconfigurable optoelectronic devices. This work represents a crucial advancement in the field of polaritonics, providing new tools for manipulating light at the nanoscale and fostering developments in quantum computing, integrated photonics, and the generation of novel quantum states of light.