2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/86947A novel open cavity formed by three 60-degree wedges of a photonic crystal with negative effective index is designed and studied. The quality factor of the open cavity can be larger than 2000. The influence of the interface termination on the resonant frequency and the quality factor is studied.8 pages, 3 figursOpticstext