Engineering Commons^™

Photonic Crystal Edge Couplers For Sensing Applications, Michael A. Zylstra

Electronic Thesis and Dissertation Repository

Microelectromechanical systems (MEMS) have not only enabled the development of inexpensive sensors but have also improved their performance by lowering their mass thus enabling faster sensor response. However, there are limitations regarding the mass-scaling of conventional MEMS sensors that prevent further miniaturization. This makes the measurement of distributed forces with high spatiotemporal resolution challenging. Optical-based sensors provide low-volume confinement of electromagnetic energy and enable further mass-scaling. This thesis investigates the application of an optical deflection sensing mechanism that relies on the position dependent coupling between dielectric-like edge states on nearby photonic crystal slabs for the purposes of acoustic pressure, wall …

Nanoplasmonic Sensors Based On Periodic Arrays Of Gold Nanoparticles, Hao Jiang

Electronic Thesis and Dissertation Repository

Nanoplasmonic sensors use the localized surface plasmon resonance (LSPR) of metal nanostructures to sense the refractive index change in a surface-bound layer caused by biomolecular interactions or changing chemical environment. In this thesis, four types of sensor configurations based on gold nanoparticle arrays are thoroughly investigated.

The first configuration is a periodic array of gold nanoparticles excited by the evanescent field of an optical waveguide mode. Since light carried by a waveguide mode propagates along the same plane of the periodicities, the coupling of nanoparticles are strongly affected by the photonic crystal lattice. This configuration is investigated both in simulations …

Optical Power Splitting Techniques Using Photonic Crystal Line Defect Waveguides, Rajat Dey

Electronic Thesis and Dissertation Repository

“Photonic Crystals (PCs)” are dielectric or metallo-dielectric structures with periodic spatial alternations of refractive index on the scale of the wavelength of light. Many optical devices, based on PCs, have been proposed. There are multiple ways by which equal amount of power of incoming signals can be divided into two, three and four output channels; for example using multiple coupled photonic crystal waveguides, directional coupling and cascaded multimode PC waveguides. Ideally, the splitter should divide the input power equally into the output channels without significant reflection or radiation losses and should be compact in size. In this thesis we have …