High-temperature cuprate superconductors exhibit extremely local nanoscale phenomena and strong sensitivity to doping. While other experiments have looked at nanoscale interfaces between layers of different dopings, we focus on the interplay between naturally inhomogeneous nanoscale regions. Using scanning tunneling microscopy to carefully track the same region of the sample as a function of temperature, we show that regions with weak superconductivity can persist to elevated temperatures if bordered by regions of strong superconductivity. This suggests that it may be possible to increase the maximum possible transition temperature by controlling the distribution of dopants.
Published in Physical Review Letters:
"Nanoscale Proximity Effect in the High-Temperature Superconductor Bi2Sr2Ca2CuO8+δ Using a Scanning Tunneling Microscope," Colin V. Parker, Aakash Pushp, Abhay N. Pasupathy, Kenjiro K. Gomes, Jinsheng Wen, Zhijun Zu, Shimpei Ono, Genda Gu, and Ali Yazdani, Physical Review Lett. 104, 117001 (2010). (Letter)
- See also Viewpoint in Physics written by Jenny Hoffman.