On-chip mode-division multiplexing switch

Abstract

Leveraging the spatial modes of multimode waveguides using mode-division multiplexing on an integrated photonic chip allows unprecedented scaling of bandwidth density for on-chip communication. Switching channels between waveguides is critical for future scalable optical networks, but its implementation in multimode waveguides must address how to simultaneously control modes with vastly different optical properties. Here we present a platform for switching signals between multimode waveguides based on individually processing the spatial mode channels using single-mode elements. Using this wavelength-division multiplexing-compatible platform, we demonstrate a 1 × 2 multimode switch for a silicon chip that routes four data channels with low < −16.8 dB crosstalk. We show bit-error rates below 10 −9 and power penalties below 1.4 dB on all channels while routing 10 Gb/s data when each channel is input and routed separately. The switch exhibits an additional power penalty of less than 2.4 dB when all four channels are simultaneously routed. These results enable individual processing of multimode signals and high-bandwidth, flexible optical networks.

Bi-Directional Coupler as a Mode-Division Multiplexer/Demultiplexer

“…The operating wavelength is 1550 nm. The corresponding coupling coefficients are evaluated from (13), (14), (17), (19), and (20).…”

“…Mode-division multiplexers (MDMs) are getting increasing interest in recent years in order to multiplex several modes in a single fiber [3], [5]- [20]. Ding et al have demonstrated an on-chip two-mode division multiplexing circuit using a tapered directional coupler-based TE 0 and TE 1 mode multiplexer and demultiplexer on the silicon-on-insulator platform [6].…”

Laguerre-Gaussian mode division multiplexing in multimode fiber using SLMs in VCSEL arrays

“…In addition, q-plates have been fabricated from liquid-crystal slabs to convert a left circularly polarized beam into a helically phased beam with right circular polarization, or vice versa [27]. Furthermore, on-plane mode couplers for combining and separating different spatial channels [28][29][30][31], switches for routing different channels [32] have also been developed.…”

Mode-Division Multiplexing for Silicon Photonic Network-on-Chip

“…Most of the functional elements for MDM networks have already been demonstrated. A WDM compatible multimode switch using single-mode microring resonator [19] and a thermal-optic Mach-Zehnder interferometer (MZI) based broadband mode switch [20] and a 4-channel silicon photonic MIMO mode unscrambler using a mesh of cascaded MZIs [21] have been demonstrated. Reference [22] described the implementation of a two-mode ring resonator based add/drop filter which has the potential for channel selective filtering in MDM systems.…”