Ultra-thin silicon/electro-optic polymer hybrid waveguide modulators

Abstract

Ultra-thin silicon and electro-optic (EO) polymer hybrid waveguide modulators have been designed and fabricated. The waveguide consists of a silicon core with a thickness of 30 nm and a width of 2 μm. The cladding is an EO polymer. Optical mode calculation reveals that 55% of the optical field around the silicon extends into the EO polymer in the TE mode. A Mach-Zehnder interferometer (MZI) modulator was prepared using common coplanar electrodes. The measured half-wave voltage of the MZI with 7 μm spacing and 1.3 cm long electrodes is 4.6 V at 1550 nm. The evaluated EO coefficient is 70 pm/V, which is comparable to that of the bulk EO polymer film. Using ultra-thin silicon is beneficial in order to reduce the side-wall scattering loss, yielding a propagation loss of 4.0 dB/cm. We also investigated a mode converter which couples light from the hybrid EO waveguide into a strip silicon waveguide. The calculation indicates that the coupling loss between these two devices is small enough to exploit the potential fusion of a hybrid EO polymer modulator together with a silicon micro-photonics device.

High‐Speed Modulator Based on Electro‐Optic Polymer Infiltrated Subwavelength Grating Waveguide Ring Resonator

“…Structural slow light, such as slot photonic crystals and plasmonic devices, can effectively shrink the phase shifter size but at the price of significantly increased insertion loss . Inspired by the success of silicon microring resonators, a few attempts have been made to replicate microrings on SOH platform through several waveguiding structures . Strip waveguides based microring resonators with EO polymer as top cladding have a radius of 40 μm .…”

Electro‐optic Polymer Ring Resonator Modulator on a Flat Silicon‐on‐Insulator

“…Furthermore, the flexible feature of polymeric materials enables a variety of structures in the hybrid silicon and polymer waveguide platform. Many types of hybrid waveguide modulators have been previously realized in the form of silicon strips, slots, and photonic crystals . Besides, ring resonators highlight the superior qualities of the device due to a compact footprint, low driving voltage, and the ability to be driven as a lumped RF element .…”

“…Many types of hybrid waveguide modulators have been previously realized in the form of silicon strips, slots, and photonic crystals. [8][9][10] Besides, ring resonators highlight the superior qualities of the device due to a compact footprint, low driving voltage, and the ability to be driven as a lumped RF element. [11,12] To date, hybrid ring structures remain problematic in reducing the propagation loss, limited bandwidth, and unsatisfied EO activities.…”

Novel poly(aryl ether ketone) with electro-optic chromophore side chains for light modulators

“…Due to their ultrafast response time, easier processing, lower dielectric constant and higher nonlinear optical coefficients compared to conventional inorganic crystals and semiconductors, organic second order nonlinear optical materials have received more and more attention for their potential applications in high speed electro-optic conversion devices [1][2][3][4][5][6][7]. The performance of electro optical (EO) devices in half-wave voltage, insertion loss and stability has increased.…”