Plasmonic Dirac-vortex lasers via three-dimensional photonic mass vortices engineering.

Topological photonic crystals provide a powerful platform for manipulating light. However, their flexibility in realizing diverse far-field beam profiles and polarization states is limited by the number of spatial symmetries lattices can provide. Here, we demonstrate plasmonic Dirac-vortex lasers with controlled polarization and intensity distributions by engineering photonic mass vortices in a three-dimensional parameter space. We design plasmonic Dirac-vortex cavities consisting of honeycomb lattices of aluminum nanoparticles, where photonic mass vortices are achieved by arranging distorted unit cells in an angular winding configuration. By manipulating the radial and azimuthal displacements of the nanoparticles as well as their size, taken as the third dimension of the system, we predict far-field radiation with spatially programmable polarization states and asymmetric intensity distributions. Experimentally, this is achieved by integrating organic dye molecules within the plasmonic Dirac-vortex cavities. Our work establishes a paradigm for multi-dimensional mass-enabled cavity engineering, which offers flexibility in sculpting exotic photonic states with broad implications for photonic circuits, quantum devices, and bosonic systems.