Lasing from a non-Bravais lattice with symmetric dielectric nanoparticles
Phys. Rev. B 113, 075147 – Published 23 February, 2026
DOI: https://doi.org/10.1103/wh8b-v3rn
Abstract
Bound states in the continuum (BICs) and surface lattice resonances (SLRs) can both provide in-plane optical feedback for lasing while enabling surface emission. However, in Bravais lattices composed of symmetric dielectric nanoparticles, lasing is typically observed only from BICs, as SLRs suffer from relatively large radiative losses and fail in the competition for gain. By introducing size detuning into a Bravais lattice, the guided modes of the original Bravais lattice are folded into the light cone of the resulting non-Bravais lattice. Among the modes within the light cone, BICs retain the same symmetry-protected characteristics as those in a Bravais lattice, whereas the quality factor of SLRs can be tuned by adjusting the extent of size detuning. We fabricated non-Bravais lattices of nanoparticles on quartz substrates and integrated them with dye molecules as the gain medium. Lasing modes were identified via angle- and polarization-resolved measurements. We observed that lasing from SLR and BIC modes emerged simultaneously, with comparable threshold values.
