Silicon photonic modulator circuit with programmable intensity and phase modulation response

TL;DR

This paper introduces a programmable silicon photonic modulator circuit capable of independently controlling intensity and phase modulation, enhancing adaptability and performance in optical communication and sensing applications.

Contribution

It presents a novel circuit-level programmable modulator design that can generate both intensity and phase modulation without platform constraints, demonstrated on silicon photonics platforms.

Findings

Demonstrates precise control over intensity and phase modulation

Surpasses traditional modulators in adaptability and performance

Enables self-calibration with on-chip monitors

Abstract

Electro-optical modulators are essential components in optical communication systems. They encode an electrical waveform onto an optical carrier. However, their performance is often limited by inherent electro-optic processes and imperfections in existing integrated designs, which limit their adaptability to diverse applications. This paper presents a circuit-level programmable modulator design that addresses these challenges. The proposed modulator can generate both intensity and phase modulation, optimizing performance without altering the underlying design or constraining platform limitations. We explain and demonstrate the principle with both carrier depletion-based modulators and SiGe electro-absorption modulators on a silicon photonic platform. Experiments demonstrate precise control and optimization capabilities surpassing those of traditional modulator designs, marking a significant leap forward in adaptability and performance enhancement across intensity, phase, and modulation linearity, enabled by programmable photonics. In combination with on-chip monitors, our circuit can be self-calibrating. This programmable modulator circuit concept can be applied to modulators in different platforms, incorporating existing phase shifter designs, and act as a drop-in replacement in more complex circuits. It has the potential to be widely used in optical communication, LiDAR, microwave photonics, and other systems, meeting the increasing demands of various applications.