A giant red shift and enhancement of the light confinement in a planar array of dielectric bars

The results of research into resonant phenomena in double-periodic subwavelength planar structures made up of paired dielectric bars are presented. For the first time the existence of high Q-factor trapped mode resonances is revealed in these low-loss entirely dielectric structures. A large red shift of the trapped mode resonance of the structure is observed as compared with the resonant wavelength of the periodic structure with only one dielectric bar per unit cell. This shift of the resonant wavelength is caused by a strong coupling of the electromagnetic fields in the adjacent dielectric bar resonators.