Until now, optical fields have been treated only as propagating waves. However, atomic-scale objects can also see the near-field. It follows that the precise fabrication of nano metallic clusters can bridge the gap between near-field and far-field, resulting in a whole new generation of optical materials and devices with precisely engineered optical properties. To achieve these goals, the precise fabrication of nano-metallic structures is required, with feature sizes on the scale of a few nanometers. A novel controlled assembly process for metallic nano-structures will combine the best features of chemical self-assembly and nano-lithography, while eliminating the disadvantages of each. This is done by doping through combined electrochemical and mechanical stimulation using a scanning probe microscope (SPM), followed by controlled nano-metal growth and/or stabilization. This controlled-assembly technique enables nanoscale positioning precision, is able to produce high-crystal-quality metal, and be reproducible, even for complex metallic structures as needed for wafer-integrated fabrication. The work will concentrate initially on optical nano-wires with widths on the order of 50 -150 nm. The research team is formed with experts in material science, and in non-linear and quantum optics and engages students in multi-disciplinary work. The impact of this could be far-reaching. For example, high order nonlinear optical and Raman interactions can be produced at milliwatt power levels. Single molecule emitters will see such large vacuum Rabi frequencies that the damping effects of spontaneous emission will become negligible. These nano-optic devices will have a wide range of DoD applications, ranging from ultra-sensitive chemical and biological sensors, to high temperature IR detectors, to novel multi-spectral focal plane arrays.
