By coating a single-mode–multimode–single-mode (SMS) structure with a complex refractive index thin-film the central wavelength of the transmission and attenuation bands of the optical spectrum can be shifted. By adequate selection of multimode segment length and diameter, the thin-film thickness and the thin-film refractive index, the sensitivity of the device to the surrounding medium refractive index, the thickness of the thin-film or the refractive index of the thin-film can be optimized. Experimental results are corroborated numerically with the transfer matrix method.
© 2013 IEEE
Ignacio Del Villar, Abian B. Socorro, Jesus M. Corres, Francisco J. Arregui, and Ignacio R. Matias, "Optimization of Sensors Based on Multimode Interference in Single-Mode–Multimode–Single-Mode Structure," J. Lightwave Technol. 31, 3460-3468 (2013)