Linear integrated optics in 3C silicon carbide.

Francesco Martini,Alberto Politi

doi:10.1364/oe.25.010735

Abstract

The development of new photonic materials that combine diverse optical capabilities is needed to boost the integration of different quantum and classical components within the same chip. Amongst all candidates, the superior optical properties of cubic silicon carbide (3C SiC) could be merged with its crystalline point defects, enabling single photon generation, manipulation and light-matter interaction on a single device. The development of photonics devices in SiC has been limited by the presence of the silicon substrate, over which thin crystalline films are heteroepitaxially grown. By employing a novel approach in the material fabrication, we demonstrate grating couplers with coupling efficiency reaching -6 dB, sub-µm waveguides and high intrinsic quality factor (up to 24,000) ring resonators. These components are the basis for linear optical networks and essential for developing a wide range of photonics component for non-linear and quantum optics.

Highlights

The development of new photonic platforms for quantum technologies poses strict requirements in the choice of optical materials, given the range of functionalities needed [1]
Quantum emitters coupled with an integrated cavity would overcome the challenge of embedding single photon sources and provide non-linear interactions between single photons, both cornerstones to achieve a multitude of quantum applications
For both structures we considered a sidewall angle of 80◦, consistent with our process technology, and a refractive index of 2.6

Summary

Introduction

The development of new photonic platforms for quantum technologies poses strict requirements in the choice of optical materials, given the range of functionalities needed [1]. “Optical nonlinearities in high-confinement silicon carbide waveguides,” Optics letters 40, 4138–4141 (2015). The high refractive index of 2.6, indispensable for deep integration of photonic components and small modal volume in resonators, together with the wide electronic bandgap of 2.3 eV, could allow efficient non-linear optics processes, like frequency conversion and non-classical generation of light, without incurring in multiple photon absorption that limits silicon quantum photonics [5, 6].

Results

Conclusion