Toward hybrid integration of exotic materials in an electronic-photonic CMOS platform via substrate removal

We demonstrate direct access to the silicon device layer of a monolithic CMOS electronics-photonics platform with a full-digital back-end-metal stack, in post-fabrication at die level, allowing the integration of functional materials (e.g. into slot waveguides).W911NF1920114 - Department of Defense/AROAccepted manuscrip

Electronic-photonic millimeter-wave sensing element based on monolithically integrated LNA and triple-cavity ring modulator

We demonstrate CMOS-integrated mm-wave-to-optical sensing elements comprising LNAs and triple-ring modulators that break the conversion-bandwidth tradeoff, showing a projected noise figure of 24 dB at 57 GHz (30 mW/element, -45dBm RF-input, 6dBm laser LO). The elements are tileable at small pitches, enabling photonic disaggregation of large-scale phased arrays.000000000000000000000000000000000000000000000000000000010759 - The Regents of the University of California (dba UniversityAccepted manuscrip

Reflectionless standing-wave operation in microring resonators

We demonstrate a scheme for microring resonators to operate as standing-wave resonators while eliminating reflections and maintaining traveling-wave-resonator-like p-n junction microring modulators to achieve higher performance than other junction geometries.Accepted manuscrip

Rapid adiabatic 3 dB coupler with 50±1% splitting over 200 nm including S, C and L bands in 45 nm CMOS platform

We demonstrate a 70 µm-long silicon rapid adiabatic coupler (RAC) with <0.07 dB insertion loss over 50 nm and power splitting ratio 50 ± 1% over 200 nm bandwidth fabricated in the commercial 45RF ‘zero change’ CMOS electronics-photonics platform.Accepted manuscrip

A monolithically integrated electronic-photonic front-end utilizing micro-ring modulators for large-scale mm-wave sensing

000000000000000000000000000000000000000000000000000000010759 - The Regents of the University of California (dba UniversityAccepted manuscrip

Silicon waveguides and resonators with sub-0.1 dB/cm propagation loss and over 7 million Q in a foundry process

Propagation loss is characterized vs. waveguide width in a 220 nm silicon photonics foundry platform to form a compact model. Test paperclips and racetrack resonators with quality factors up to 7.6 million reveal losses as low as 0.064 dB/cm.Accepted manuscrip

Photonic molecule electro-optic modulators for efficient, widely tunable RF sideband generation and wavelength conversion

We propose photonic molecule electro-optic modulators with tunable supermode splitting for efficient widely tunable RF sideband generation. Using an auxiliary tunable off-resonant cavity as a variable coupler maintains a high Q/V.Accepted manuscrip

Fine-Resolution Silicon Photonic Wavelength-Selective Switch Using Hybrid Multimode Racetrack Resonators

In this work, we describe a procedure for synthesizing racetrack resonators with large quality factors and apply it to realize a multi-channel wavelength-selective switch (WSS) on a silicon photonic chip. We first determine the contribution of each component primitive to propagation loss in a racetrack resonator and use this data to develop a model for the frequency response of arbitrary order, coupled-racetrack channel dropping filters. We design second-order racetrack filters based on this model and cascade multiple such filters to form a 1x7 WSS. We find good agreement between our model and device performance with second-order racetrack that have ~1 dB of drop-port loss, ~2 GHz FWHM linewidth, and low optical crosstalk due to the quick filter roll-off of ~ 5.3 dB/GHz. Using a control algorithm, we show three-channel operation of our WSS with a channel spacing of only 10 GHz. Owing to the high quality factor and quick roll-off of our filter design, adjacent channel crosstalk is measured to be <-25 dB for channels spaced on a 10 GHz grid. As a further demonstration, we use five of seven WSS channels to perform a demultiplexing operation on both an 8 GHz and a 10 GHz grid. These results suggest that a low-loss WSS with fine channel resolution can be realized in a scalable manner using the silicon photonics platform