SURFACE-PLASMON EXCITATION USING A POLARIZATION-PRESERVING OPTICAL-FIBER AND AN INDEX-MATCHING FLUID OPTICAL-CELL

Existing experimental configurations to excite surface plasmons are re viewed, and a new experimental method for exciting surface plasmons is described. A transverse magnetic polarized wave is guided by a polari zation-preserving optical fiber, collimated by a gradient-index lens, and launched into an optical cell filled with index-matching fluid. Th e wave is reflected off of a rotating mirror and excites a surface pla smon on a dielectric-metal interface by attenuated total reflection. T he reflectance and incidence angles are measured simultaneously with a position-sensitive photodiode. The main advantages of this new method , compared with existing methods, are the low equipment costs and the ease with which a variety of surface-plasmon experiments can be perfor med.