Selective excitation of fiber-modes using surface plasmons

Experimental and theoretical results are presented on a surface plasmon fiber device that provides selective excitation of individual modes in a dual-mode optical fiber. Using prism coupling to probe this device, good modal discrimination was obtained experimentally for the LP/sub 1/1 fiber mode. The LP/sub 1/1 modal discrimination, however, was found to be inherently limited by the field distribution characteristics of the dual-mode fiber. Applications are to fixed and tunable mode tap or couplers.<
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