Silicon photonics has been largely developed as a platform to address the future challenges in several applications including datacom, sensing or optical communications, among others. However, the properties of silicon itself is not enough to overcome all limitations in terms of speed, power consumption and scalability. Especially, silicon exhibits strong two photon absorption (TPA) and is centrosymmetric limiting the use of its nonlinear optical properties including Kerr and Pockels effects. New strategies have then been encouraged based on the heterogeneous integration of new materials in the silicon photonics platform. In this perspective, the recent trends in the development of new materials with optical properties complementary to the silicon and silicon nitride properties will be presented. In particular, the presentation will focus in a new integration approach of doped crystalline-oxides on silicon and silicon nitride photonics platform. Especially, the integration of doped-zirconia (ZrO2), compatible with CMOS technology has been developed. Indeed, such an oxide exhibits linear and nonlinear optical properties suitable to address the challenges of silicon photonics: low propagation loss, no two-photon absorption (TPA) due to its large bandgap energy, a large transparency window from the ultraviolet to the mid-infrared, Kerr and Pockels effect, and light emission.

We study the antimony trisulfide’s (Sb2S3) linear optical properties for potential applications in reconfigurable chip-based supercontinuum mid-IR sources. We experimentally demonstrate that Sb2S3 cladding on SiGe-on-Si waveguides induces relatively low extra propagation loss below 1 dB/cm between 3.3 and 3.9 μm wavelength.

Since their first demonstration more than 15 years ago, subwavelength metamaterials in silicon photonic devices have attracted increasing research interest while also breaking into commercial applications. We will discuss recent advances in this research field, in particular novel components and circuits for beam steering applications, on-chip filtering and quantum optics. The use of Mie resonant particle chains as on-chip waveguides has only recently been demonstrated and is opening the door to a new and exciting branch of integrated metamaterials research. We will review the early work in this area.

Recently, we successfully realized amorphous silicon carbide (a-SiC) integrated photonics with

optical losses as low as 0.78 dB/cm. Moreover, the deposition of a-SiC was done at 150 ℃, which enables

successful lift of a-SiC as an additive step to existing photonics circuits. In this work, we present an adiabatic

taper coupler which provides bidirectional lossless connection between two integrated photonics platforms:

thin-film silicon nitride (Si3N4) and a-SiC. Normalized power transmission of 96.61% is presented, and the

coupler enables strong confinement when coupling from weakly confined thin-film device to normal thickness

device. By utilizing such a coupler as bridge, switching back and forth between Si3N4 and a-SiC platforms

can be easily realized. This allow us to carry out applications including quantum interference and digital

Fourier spectroscopy, in which long optical delay lines are constructed on Si3N4 and highly integrated circuits

are built on a-SiC.