Electrically packaged silicon-organic hybrid (SOH) I/Q-modulator for 64 GBd operation

TL;DR

This paper presents a novel electrical packaging method for silicon-organic hybrid I/Q modulators, enabling high-speed optical communication at 64 GBd, advancing their practical deployment.

Contribution

The work introduces a high-density RF packaging approach for SOH modulators, demonstrating high-speed data transmission and bridging the gap from proof-of-concept to commercial use.

Findings

Achieved 128 Gbit/s line rate with QPSK modulation.

Demonstrated 160 Gbit/s with 16QAM modulation.

Validated the packaging concept with high-speed optical signals.

Abstract

Silicon-organic hybrid (SOH) electro-optic (EO) modulators combine small footprint with low operating voltage and hence low power dissipation, thus lending themselves to on-chip integration of large-scale device arrays. Here we demonstrate an electrical packaging concept that enables high-density radio-frequency (RF) interfaces between on-chip SOH devices and external circuits. The concept combines high-resolution $\mathrm{Al_2O_3}$ printed-circuit boards with technically simple metal wire bonds and is amenable to packaging of device arrays with small on-chip bond pad pitches. In a set of experiments, we characterize the performance of the underlying RF building blocks and we demonstrate the viability of the overall concept by generation of high-speed optical communication signals. Achieving line rates (symbols rates) of 128 Gbit/s (64 GBd) using quadrature-phase-shiftkeying (QPSK) modulation and of 160 Gbit/s (40 GBd) using 16-state quadrature-amplitudemodulation (16QAM), we believe that our demonstration represents an important step in bringing SOH modulators from proof-of-concept experiments to deployment in commercial environments.