Thick waveguides of low-stress stoichiometric silicon nitride on sapphire (SiNOS).

Low-stress stoichiometric silicon nitride (SiN) waveguides with an unprecedented thickness of up to 1350 nm and a width in the range of 2.2 - 2.7 µm are fabricated using a single LPCVD step on sapphire substrates (SiNOS).

High on-chip gain spiral AlO:Er waveguide amplifiers.

We demonstrate reactively sputtered AlO:Er waveguide amplifiers with an erbium concentration of 3.9 × 10 ions/cm, capable of achieving over 30 dB small signal net gain at 1532 nm using bidirectional pumping at 1480 nm. We observe on chip output powers of 10.

Octave-spanning supercontinuum generation in a CMOS-compatible thin SiN waveguide coated with highly nonlinear TeO.

Supercontinuum generation (SCG) is an important nonlinear optical process enabling broadband light sources for many applications, for which silicon nitride (SiN) has emerged as a leading on-chip platform. To achieve suitable group velocity dispersion and high confinement for broadband SCG the SiN waveguide layer used is typically thick (>∼700 nm), which can lead to high stress and cracks unless specialized processing steps are used. Here, we report on efficient octave-spanning SCG in a thinner moderate-confinement 400-nm SiN platform using a highly nonlinear tellurium oxide (TeO) coating.

Hybrid silicon-tellurium-dioxide DBR resonators coated in PMMA for biological sensing.

We report on silicon waveguide distributed Bragg reflector (DBR) cavities hybridized with a tellurium dioxide (TeO) cladding and coated in plasma functionalized poly (methyl methacrylate) (PMMA) for label free biological sensors. We describe the device structure and fabrication steps, including reactive sputtering of TeO and spin coating and plasma functionalization of PMMA on foundry processed Si chips, as well as the characterization of two DBR designs via thermal, water, and bovine serum albumin (BSA) protein sensing. Plasma treatment on the PMMA films was shown to decrease the water droplet contact angle from ∼70 to ∼35°, increasing hydrophilicity for liquid sensing, while adding functional groups on the surface of the sensors intended to assist with immobilization of BSA molecules.

Social functioning and brain imaging in individuals at clinical high-risk for psychosis: A systematic review.

Impairments in social functioning are a core impairment in psychosis and are associated with poor outcomes. These deficits are found in those at clinical high-risk (CHR) for psychosis, and can persist even in the absence of transition. However, the neurobiological underpinnings of social functioning remain unclear, therefore we conducted a systematic review of brain metrics that have been associated with social functioning in youth at CHR for psychosis.