Crystalline Oxides Platform for Hybrid Silicon Photonics

Introduction

Silicon (Si) photonics stands as a solid candidate to address the scaling challenges of emerging communication systems with an ever-growing number of interconnected devices. However, Si has major physical limitations that prevent on-chip integration of key functions: strong two-photon absorption limiting nonlinear optical devices, Si centrosymmetry preventing fast optical modulation, and an indirect bandgap nature hindering light emission and amplification.

Limitations of Silicon Photonics

The common solution to overcome these limitations is the hybrid integration of various materials on Si, each addressing one specific limitation. However, this strategy requires a dedicated technology for each material to be integrated, which compromises cost and scalability.

Project Overview

In this context, the CRYPTONIT project will explore a new paradigm for Si photonics based on the hybrid integration of multifunctional zirconia-based crystalline oxides (c-oxides), providing several physical properties non-existent in Si: strong nonlinearities, ferroelectricity, and light amplification.

Hybrid Superlattices Development

The original idea is to develop hybrid superlattices, comprising multiple nano-scale layers of different c-oxides to combine key optical functionalities, using a common Si-compatible fabrication process.

Focus and Objectives

The project will focus on the demonstration of advanced nonlinear and optoelectronic devices on Si, operating in the near-infrared for the development of highly-efficient and broadband photonic integrated circuits. The main objectives are:

1. The development of a hybrid Si photonics platform based on multifunctional c-oxide superlattices.
2. The demonstration of high power and broadband frequency comb sources (strong nonlinearities and amplification).
3. The demonstration of high-speed >100 GHz optical modulators based on the Pockels effect (ferroelectricity).

Impact

These objectives are ground-breaking in nature and will open new horizons for research and applications in communications, sensing, and quantum photonics.