High-extinction ratio and low-loss silica-based 8/spl times/8 thermooptic matrix switch

A high-extinction ratio and low-loss silica-based 8/spl times/8 thermooptic matrix switch is demonstrated. The 8/spl times/8 matrix switch is realized by using a double Mach-Zehnder interferometer switching unit and a matrix arrangement which reduces the total waveguide length. The average extinction ratio and the average insertion loss are 60.3 and 5.2 dB, respectively.