CMOS-compatible, piezo-optomechanically tunable photonics for visible wavelengths and cryogenic temperatures

Low loss GaN waveguides at the visible spectral wavelengths for integrated photonics applications.

We perform comprehensive studies on the fundamental loss mechanisms in III-nitride waveguides in the visible spectral region. Theoretical analysis shows that free carrier loss dominates for GaN under low photon power injection. When optical power increases, the two photon absorption loss becomes important and eventually dominates when photon energy above half-bandgap of GaN. When the dimensions...

Electronic Devices Fabricated at Cmos Backend-compatible Temperatures

Ge microdisk with lithographically-tunable strain using CMOS-compatible process.

We present germanium microdisk optical resonators under a large biaxial tensile strain using a CMOS-compatible fabrication process. Biaxial tensile strain of ~0.7% is achieved by means of a stress concentration technique that allows the strain level to be customized by carefully selecting certain lithographic dimensions. The partial strain relaxation at the edges of a patterned germanium microd...

Integrated TiO2 resonators for visible photonics.

We demonstrate waveguide-coupled titanium dioxide (TiO(2) racetrack resonators with loaded quality factors of 2.2×10(4) for the visible wavelengths. The structures were fabricated in sputtered TiO(2) thin films on oxidized silicon substrates using standard top-down nanofabrication techniques, and passively probed in transmission measurements using a tunable red laser.

Electrooptical measurement system for the DC characterization of visible detectors for CMOS-compatible vision chips

An electro-optical measurement system for the DC characterization of visible detectors for CMOS compatible vision chips is presented which can help designers to characterize these detectors. The measurement system has been designed to be versatile, fast and easily expandable and used. Two different set-up's for the measurement of the spectral response and the optical dynamic range of the detect...