Light-tuned superconductors

A major focus of superconductor research is manipulating the critical temperature of various superconducting materials. The properties of such materials could be very beneficial, but most materials only become superconducting below a certain (very cold) temperature. Prof. Yoram Dagan of Tel Aviv University has recently demonstrated a way to control this critical temperature by simply changing the light shone on a particular material. Their process coats a thin layer of superconductor with a one-molecule-thick layer of organic molecules. The light impinges on the surface of these materials, the organic molecules change their shape on the surface, in turn changing the critical temperature of the material. The researchers could raise the materials' critical temperature by shining high-energy, ultra-violet light on it, and could lower it by shining visible light.