SURFACE-PLASMON POLARITIONS IN THIN METAL-FILMS AND THEIR ROLE IN FIBER OPTIC POLARIZING DEVICES

The polarization selective evanescent field coupling of an optical wave in a 1.3-μm fiber to surface plasmon polaritons supported by a thin aluminum film was investigated theoretically and experimentally. Good agreement was observed between the theoretically predicted conditions for efficient coupling and the experimentally determined conditions for high TM/TE extinction ratio of the optical field. In addition, the use of silver and chrome in this role was investigated experimentally at 1.3 μm, and 0.63-μm devices were studied using aluminum. The results of this work led to the realization of readily manufacturable, high-extinction-ratio (>50 dB) low-loss (<0.5 dB) fiber optic polarizers and polarizing couplers in standard and highly birefringent fiber. © 1990 IEEE