  We report the fabrication of high Tc superconducting wires by photodoping a
GdBa2Cu3O{6.5} thin film. An optical near-field probe was used to locally
excite carriers in the system at room temperature. Trapping of the
photogenerated electrons define a confining potential for the conducting holes
in the CuO planes. Spatially resolved reflectance measurements show the
photogenerated nanowires to be ~ 250 nm wide. Electron diffusion, before
electron capture, is believed to be responsible for the observed width of the
wires.

Superconductivity;Mesoscale and Nanoscale Physics