Ultra-High Electro-Optic Activity Demonstrated in a Silicon-Organic Hybrid (SOH) Modulator

TL;DR

This paper demonstrates a silicon-organic hybrid modulator with the highest in-device electro-optic figure of merit to date, enabling ultra-fast, low-voltage optical communication at 40 Gbit/s.

Contribution

The study introduces a novel SOH Mach-Zehnder modulator with record-breaking electro-optic performance and low drive voltage, advancing high-speed optical modulation technology.

Findings

Achieved an in-device EO figure of merit of 2300 pm/V.

Demonstrated 40 Gbit/s data transmission with high Q factors.

Realized a low {5}-voltage of 210 mV in a 1.5 mm device.

Abstract

Efficient electro-optic (EO) modulators crucially rely on advanced materials that exhibit strong electro-optic activity and that can be integrated into high-speed and efficient phase shifter structures. In this paper, we demonstrate ultra-high in-device EO figures of merit of up to n3r33 = 2300 pm/V achieved in a silicon-organic hybrid (SOH) Mach-Zehnder Modulator (MZM) using the EO chromophore JRD1. This is the highest material-related in-device EO figure of merit hitherto achieved in a high-speed modulator at any operating wavelength. The {\pi}-voltage of the 1.5 mm-long device amounts to 210 mV, leading to a voltage-length product of U{\pi}L = 320 V{\mu}m - the lowest value reported for MZM that are based on low-loss dielectric waveguides. The viability of the devices is demonstrated by generating high-quality on-off-keying (OOK) signals at 40 Gbit/s with Q factors in excess of 8 at a drive voltage as low as 140 mVpp. We expect that efficient high-speed EO modulators will not only have major impact in the field of optical communications, but will also open new avenues towards ultra-fast photonic-electronic signal processing.