3×10 Gb/s silicon three-mode switch with 120° hybrid based unbalanced Mach-Zehnder interferometer

We propose and experimentally demonstrate a reconfigurable mode division multiplexing (MDM) silicon photonics three-mode switch (3MS) in C-band using a 120° optical hybrid based unbalanced Mach-Zehnder interferometer (UMZI) and Ti/W metal heater phase-shifter. The novel 3MS enables reconfigurable switching of the first three transverse electric (TE) modes by exploiting the relative phase difference of the 120° hybrid. A proof-of-concept realization of this 3MS demonstrates <12.0 μs switching time and >12.3 dB switching extinction ratio at 1560 nm wavelength with 94.8 mW average heater power consumption. Simultaneous (de)multiplexing and switching of 10 Gb/s non-return-to-zero (NRZ) PRBS31 optical payload over three spatial channels experimentally demonstrates 3 ×10 Gb/s aggregated bandwidth. Open eye diagrams in all output channels with >9.6 electrical signal-to-noise ratio (SNR) exhibits reliable data transmission. The 3MS has potential applications in MDM silicon photonics interconnects for the implementation of high throughput switch matrix.