2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/84679The Bragg regime shifts when conventional materials in a multilayer distributed Bragg reflector (DBR) are replaced by artificial materials with the so-called negative index of refraction. This provides an avenue for characterizing the latter class of materials.8 pages, 3 figuresClassical PhysicsGeneral Physicstext