Nano-dimensional patterning of YBCO for AC Loss Conductors

The main objective of the proposed Phase I project is to demonstrate a simple, scalable process to produce multiple, highly oriented, and longitudinally aligned 50-1000 nm wide YBCO filaments on Ni based tapes for efficient power generation application.The proposed process will take advantage of the well-known property that even a single monolayer of contamination is often sufficient to prevent epitaxial growth. A simple nano-stamp approach will be used to transfer contaminant onto the surface in afilament pattern prior to YBCO growth. We will produce nano-stamps with a range of dimensions from 100 to 1000 nm, and develop a device for reproducibly pressing the nano-stamp against a tape surface. Using this device and the nano-stamp, a very thin layerof chemical contaminant will be transferred onto either a Ni-based tape or onto a buffer-layer-coated tape. Epitaxial buffer layers will be deposited using reactive magnetron sputtering. We will then show that epitaxial growth is prevented by thecontamination, under conditions where good-quality epitaxial growth is achieved on uncontaminated surfaces.The proposed HTS coated conductor structure will allow fabrication of low loss AC conductor which can be incorporated into various power generationdevices for military use such as 1 megawatt superconducting generator. The development of proposed nanotechnology will enable new fabrication concepts for variety of microelectronic, optoelectronic and biotechnological nano-devices in the commercialsector.