Silicon Carbide and Diamond: Materials and photonics

We fabricate photonic devices out of silicon carbide and introduce defect color centers into these materials to characterize their optical and spin properties in optical cavities. We also characterize the material properties of silicon carbide materials and develop optimized processing methods to fabricate high quality optical nano-cavities.

In addition, we study the optical and spin behavior of color centers introduced into a variety of diamond materials via different processing methods.

GaN: Increasing efficiency of blue emission from GaN

This work focuses on the design and fabrication of optical cavities with InGaN quantum dots as emitters. These emitters have many advantages over other III-V systems due to their high bandgap/exciton binding energy/oscillator strength/etc. which should allow for room temperature operation of novel quantum devices emitting at visible wavelengths. Such material is relatively new however and there are challenges in the material quality and fabrication of such devices. We investigate GaN photonic crystal and microdisk cavities in order to access and overcome such challenges.

Two-Dimensional Materials

We study the optical and material properties of 2D semiconductors such as molybdenum disulfide (MoS₂) with novel substrates. We additional study the fundamental interactions of these 2D materials with nano-scale optical cavities to modulate and enhance the 2D material light emission.

Lanthanide Emitters

Trivalent lanthanides provide stable emission sources at wavelengths spanning the ultraviolet through the near infrared with uses in telecommunications, lighting, and biological sensing and imaging. We have developed a method for incorporating an organometallic lanthanide complex within polyelectrolyte multilayers, producing uniform, optically active thin films on a variety of substrates. These films demonstrate excellent emission with narrow linewidths, stable over an extended eperiod of time, even when bound to metal substrates. Utilizing different lanthanides such as europium and terbium, we are able to tune the resulting wavelength of emission of these thin films. We demonstrate the suitability of this platform as a thin film emitter source for a variety of photonic applications such as waveguides, optical cavities, and sensors.

Plasmonic Materials and Optical Nano-cavities

We are developing metallic resonators to enhance spontaneous emission from various emitters including organic molecules, nano-crystals, and semiconductor quantum confined structures. Research includes design of metallic nanostructures for better control over plasmonic resonances, development of nanofabrication techniques for metallic geometries, and characterization of emitter dynamics under concentrated optical field.

ZnO: Functional 3D nanostructures for optoelectronics

Investigation and engineering of aqueously grown zinc oxide for optoelectronic applications. Shape and morphology can be controlled through solution chemistry, template growth, and top-down fabrication methods. Fabricated structures include 1D nanowires, 2D thin films, and arbitrary 3D shapes.