Nicholas X Fang
Description of Current Research
Professor Fang seeks to bridge new frontiers in nanophotonics and nanomanufacturing. His research group concentrates on creating devices for focusing photon and sound into nanometer scale and using them for imaging and nanofabrication. These devices and technologies could lead revolutionary methods of diagnosing living cells at molecular scale details, without the use of an electron microscope, and open the door for the non-destructive screening of drugs and other biological materials.
Inspired by recent scientific predictions of a series of artificial materials possessing negative index of refraction, Professor Fang's team aims at breaking the resolution limit set by light and sound waves because of their nature of diffraction. Using a thin and smooth silver film that resonantly transfer molecular scale details, Professor Fang and his group showed for the first time a sharp optical image with 30nm resolution, about 10 times better than the resolving power of state-of-the-art optical microscopes. Given that many proteins and enzymes are visible in the 50 nanometer range, the technique would allow scientists to view the transport of individual proteins and enzymes within living cells. His group is currently collaborating with Dr. Ling-Gang Wu, a leading neuron scientist from the National Institute of Health to reveal the real-time dynamics of single synapse using optical nanoscopes.
To achieve the ultimate goal of super-resolution optical imaging and information processing, a patterning tool needs to be developed to replicate complex metallic structures at the nanoscale. For this purpose, Professor Fang's group worked with Professor Placid Ferreira's group to invent an effective electrochemical imprinting tool with sub-20 nanometer resolution. The process uses a patterned solid electrolyte as a stamp; patterns are etched onto metallic film via an electrochemical reaction. This will also lead to simple and robust process steps for replication of complex metallic nanodevices, such as electronic interconnects, waveguides and sensors. Teamed up with Hewlett-Packard and Berkeley, Professor Fang's group will design, fabricate and demonstrate high speed optical modulators made with negative index materials.
His group is also collaborating with Dr. Chris Spadaccini at Livermore National Laboratory to develop advanced micro- and nanofabrication technologies for functional materials such as polymer and ceramic shells with graded density. A digital data projector in his lab has been converted into a low cost, high throughput and flexible microfabrication system for this purpose. Complex micro-reactors with embedded microchannels are fabricated for cultivating microbe and other vital tissues, and enhanced oxygenation and continuous biofuel production are demonstrated.