16 × 16 Silicon Optical Switch Based on Dual-Ring-Assisted Mach–Zehnder Interferometers

In this paper, we report a nanosecond 16 × 16 silicon electro-optic switch chip based on a Benes architecture. The switch adopts dual-ring-assisted Mach-Zehnder interferometers as the basic building blocks. In each switch element, both TiN microheaters and PIN diodes are integrated for ring resonance alignment and high-speed switching, respectively. A transfer-matrix-based theoretical model is established to analyze the switch performances. The 16 × 16 switch is characterized by measuring the optical transmission spectra and quadrature phase-shift keying (QPSK) data transmission through 16 representative optical paths. The insertion loss of the entire switch chip is 10.6 ± 1.7 dB and the crosstalk is less than -20.5 dB. The 32-Gb/s QPSK signal is successfully switched to different destination ports by reconfiguring the optical paths, verifying the signal integrity after switching.