Hannah R. Grant

Cobalt ferrite nanoparticles polymer composites based all-optical magnetometer

A method has been developed to prepare cobalt ferrite particle core polymer shell nanoparticles. These engineered nanoparticles can be further embedded into a polymer host matrix to develop highly transparent polymer based magneto-optic materials. A proof-of-principle all-optical magnetometer has been constructed based on the cobalt ferrite core polymer shell based nanocomposite material. A noise equivalent magnetic field sensitivity of 50nT/√Hz was observed using a 3μT 500Hz control magnetic field.

Flip Chip Packaging of Digital Silicon Photonics MEMS Switch for Cloud Computing and Data Centre

We report on the flip chip packaging of Micro-Electro-Mechanical System (MEMS)-based digital silicon photonic switching device and the characterization results of 12 × 12 switching ports. The challenges in packaging N² electrical and 2N optical interconnections are addressed with single-layer electrical redistribution lines of 25 <italic>μ</italic>m line width and space on aluminum nitride interposer and 13° polished 64-channel lidless fiber array (FA) with a pitch of 127 <italic>μ</italic>m. 50 <italic>μ</italic>m diameter solder spheres are laser-jetted onto the electrical bond pads surrounded by suspended MEMS actuators on the device before fluxless flip-chip bonding. A lidless FA is finally coupled near-vertically onto the device gratings using a 6-degree-of-freedom (6-DOF) alignment system. Fiber-to-grating coupler loss of 4.25 dB/facet, 10^–11 bit error rate (BER) through the longest optical path, and 0.4 <italic>μ</italic>s switch reconfiguration time have been demonstrated using 10 Gb/s Ethernet data stream.

High dynamic range microscope infrared imaging of silicon nanophotonic devices

A noninvasive diagnostic technique based on wavelength-resolved and magnified infrared images of weakly scattered light from a silicon photonic device may be useful to infer component characteristics, such as waveguide-resonator coupling, loss, quality factor, etc., at multiple locations, without the constraint of input/output couplers. Here, we demonstrate the benefit of high dynamic range microscope imaging for a silicon coupled microresonator device.

Bit error rate measurements of a 4 × 4 Si-Photonic switch using synchronous and asynchronous data

The bit error rate (BER) of a 4 × 4 Si-Photonics switch chip is characterized using four independent 10-Gb/s datastreams that are clock-synchronous or clock-asynchronous in a FPGA-based system test bed. Clear effects on the BER were seen as a result of on-chip crosstalk.

Characterization of a silicon-photonic multi-wavelength power monitor

We describe the design and operation of a silicon-photonic device for monitoring power variations of individual channels in a multi-wavelength DWDM network. Amplitude variations of ~20 dB, for channels spaced by 100 GHz, are measured.

New materials for magneto optic in-fiber and waveguide isolators

We report recent advances in new magneto optic materials including novel colorless magnetic ionic liquids and magnetic nanoparticle-core polymer-shell nanocomposites for non-reciprocal in-fiber and waveguide operation for isolation and circulation.