A novel adiabatic mode multiplexer enables a 2×2 optical switch whose operation does not depend on accumulated phase due to evanescent coupling between waveguides. The adiabatic mode multiplexer has a negligible insertion loss over C+L bands and modal cross talk better than −40 dB for any polarization state. Mode multiplexing is achieved by adiabatic transition from the fundamental mode of the single-mode waveguide to the higher mode of the multimode waveguide. Experimental measurement results for a device realized in silica-on-silicon technology are presented. By directly measuring the nonadiabatic transition probability, we show that the adiabatic mode multiplexer operates in the Landau-Zener regime.
© 2005 Optical Society of America
E. Narevicius, R. Narevich, Y. Berlatzky, I. Shtrichman, G. Rosenblum, and I. Vorobeichik, "Adiabatic mode multiplexer for evanescent-coupling-insensitive optical switching," Opt. Lett. 30, 3362-3364 (2005)