Surface lattice resonance (SLR) lasers provide a promising platform for low-threshold, large-area coherent emission through collective coupling between localized surface plasmon resonances and lattice diffraction modes. However, low-threshold room-temperature operation remains fundamentally limited in plasmonic systems due to competing metallic absorption, radiative leakage, and lateral diffraction losses within the cavity. Compared with conventional dye-based gain media, the multiple quantum well (MQW) platform offers improved material stability and reproducibility. Here we demonstrate room-temperature SLR lasing at 930 nm by integrating a dielectric multiple-quantum-well gain medium with periodic metallic nanoparticle arrays. Rather than relying solely on Q-factor analysis, we establish that modal selection and threshold behavior are governed by geometry-dependent redistribution of dissipation channels. By systematically varying the metal filling factor, lattice constant, and nanoparticle geometry including circular, square, and rectangular shapes, we reveal that different lattice symmetries modify lateral coupling coefficients and lift modal degeneracy, thereby reshaping the balance among metallic absorption, radiative feedback, and lateral leakage. Among the investigated configurations, the square geometry with a filling factor of 10% achieves the lowest threshold of 0.059 MW/cm² and a linewidth of 1 nm. Our results demonstrate that gain-loss engineering through κ-mediated lateral coupling control provides an effective strategy to regulate modal dissociation and minimize effective cavity loss in plasmonic SLR lasers.
- Gain-Loss Engineering in Geometry-Controlled Surface Lattice Resonance Lasers
- Wen-Hsuan Hsieh - National Yang Ming Chiao Tung UniversityKuo-Bin Hong - Semiconductor Research Center, Hon Hai Research Institute, Taipei City, TaiwanYu-Yuan Chien - National Yang Ming Chiao Tung UniversityKuo-Ping Chen - National Tsing Hua UniversityChia-Yen Huang - National Yang Ming Chiao Tung UniversityTien-Chang Lu - National Yang Ming Chiao Tung University
- IEEE; PISCATAWAY
- 8
- Minister of Science and Technology (MOST) of Taiwan: MOST 113-2221-E A49 067-MY3
Thiswork was supported by the Minister of Science and Technology (MOST) of Taiwan under Contract MOST 113-2221-E A49 067-MY3
- Journal article
- 22/06/2026
- IEEE journal of selected topics in quantum electronics, Vol.32(3), pp.1-8
- English