Invited - Nonlinear plasmonics in 2D nanoribbons and heterostructures

We explore the nonlinear optical properties of graphene and phosphorene nanoribbons using ab initio modeling and self-consistent perturbation theory. These two-dimensional materials exhibit significant potential for frequency conversion, optical modulation, and ultrafast signal processing due to their inherent nonlinear responses and tunable plasmonic characteristics. Our investigations reveal that graphene nanoribbons (GNRs) photoexcited by intense ultrashort optical pulses exhibit strong transient nonlinear optical responses driven by thermally activated plasmons, demonstrating a robust, non-invasive method for achieving tunable nonlinear effects without the need for excessive charge carrier doping. In a parallel study, we investigate enhanced nonlinear interactions in nanoribbon heterostructures, where the synergetic combination of tunable plasmons and anharmonic electron dispersion in graphene and phosphorene offers unique opportunities for device engineering.