Abstract

Thin-film dielectric waveguides incorporating one or more periodic elements exhibit sharp variations of the externally propagating fields at certain values of the wavelength and angle of incidence that allow coupling of the incident beam to a leaky mode of the waveguide^1,2. Theoretical studies indicate that with appropriate choice of materials and geometrical parameters, this guided-mode resonance (GMR) effect can be exploited to design polarized, narrowband reflection filters with efficiencies of 100%³,⁴. As practical applications of a filter device with such properties abound⁵,⁶, there is ample motivation for pursuing experimental proofs of these theoretically-predicted characteristics. For example, using a GMR mirror as a polarizing output coupler in a laser may require high-efficiency reflection approaching 100% with corresponding mirror transmission of a few percent yielding the laser output light⁷. During the past few years, experimental resonance efficiencies exceeding 90% have been reported.⁸–¹⁰ In this paper, a resonance filter with peak efficiency of 98% is presented and its use as output coupler in a laser cavity demonstrated.

© 1998 Optical Society of America