Fiber-to-Fiber Optical Switching Based on Gigantic Bloch-Surface-Wave-Induced Goos–Hanchen Shifts

Fiber-to-fiber on-off optical switching based on the gigantic Goos-Hanchen (GH) shift on an optical beam induced by the Bloch surface wave is experimentally demonstrated for the first time. Through changing the refractive index of the cladding covering a truncated 1-D photonic crystal, the enhanced GH shift can be toggled dynamically from zero to submillimeter range. By using the finite coupling aperture of the fiber and selecting an optimized pass region of the beam to the output fiber, high extinction ratio can be achieved with reasonable insertion loss. It is also demonstrated that a refractive index change of <; 2*10
^-3
is sufficient to realize the switching, which opens the way to realize faster and more compact integrated GH switches.