Grant: Discovery Grants Program - Individual

All-optical data processing as an alternative to electronic data processing is critical to the telecommunications and computing fields, due to the theoretically orders-of-magnitude increase in operating speed. To realize this technology in a compact platform, nonlinear (NL) waveguide photonics are used. Here, an optical ""pump"" beam alters the physical environment of an optical data pulse, causing it to be passed, blocked, re-directed, etc.; the degree of NL response is proportional to the power density of the pump. Unfortunately, photonic waveguides have a minimum size that is limited by physical considerations, requiring unacceptably high pump powers in order to produce a useful NL response. Plasmonic waveguides, however, can confine optical fields into a cross-section that is one to two orders of magnitude smaller, facilitating NL effects at correspondingly reduced powers. These unique structures manipulate surface plasmon polaritons (SPPs) - rather than photons - at the nanoscale (a SPP results from the coupling of the electromagnetic field with oscillating electrons at the surface of a metal.) The goal of my research is to design nonlinear plasmonic waveguide (NLPW) devices for applications in low-power all-optical logic and data routing. This program aims to address numerous fundamental and applied aspects of NLPW technology. Particular issues that must be resolved include: how can we ensure the existence of guided NL plasmonic modes in the frequency/intensity regime of interest? What materials and SPP frequencies are best suited for NLPWs, both in terms of device functionality and technological feasibility? What figures of merit can best describe NLPW devices, and how are they optimized in the waveguide design stage? What assumptions of photonics modeling are no longer valid in the plasmonic realm, and how can these be properly modified? Is there a fundamental limit to the confinement of SPPs? As these and other questions are answered, the realization of NLPW devices is certain to revolutionize the fields of telecommunications and computing.