Aalto Quantum Physics -seminaari: Symmetry, dynamics and topological phenomena in plasmonic nanoarrays
Periodic arrays of metallic nanoparticles couple well to adjacent quantum emitters and provide a platform for achieving coherence, enabling such phenomena as lasing or Bose-Einstein condensation. I will briefly present our recent study on lasing at the high-symmetry points of the Brillouin zone in a honeycomb plasmonic lattice. We use symmetry arguments to define singlet and doublet modes at the $\Kp$-points of the reciprocal space. We experimentally demonstrate lasing at the $\Kp$-points that is based on plasmonic lattice modes and two-dimensional feedback. By comparing polarization properties to $T$-matrix simulations, we identify the lasing mode as one of the singlets with an energy minimum at the $\Kp$-point enabling feedback. Recently, there have been considerable efforts in developing plasmonic nanoarrays which would demonstrate non-trivial topological properties. I will cover some of the approaches in pursuing that goal and the main challenges, specific for plasmonic systems.