About cookies on this site Our websites require some cookies to function properly (required). In addition, other cookies may be used with your consent to analyze site usage, improve the user experience and for advertising. For more information, please review your options. By visiting our website, you agree to our processing of information as described in IBM’sprivacy statement. To provide a smooth navigation, your cookie preferences will be shared across the IBM web domains listed here.
Publication
Journal of Vacuum Science and Technology A: Vacuum, Surfaces and Films
Paper
Studies of superconductors using a low-temperature, high-field scanning tunneling microscope
Abstract
We have developed a scanning tunneling microscope (STM) capable of operating at temperatures as low as 0.4 K and fields as high as 8 T. We have used this STM to study the energy gap of the high- Tc superconductors La-Sr-Cu-O and Y-Ba-Cu-O. We find that the reduced gap for these oxide superconductors falls in the range 3 < 2A/kB Tc < 7, for polycrystalline, single-crystal, and thin-film samples. We have also simultaneously imaged the surface topography and superconducting energy gap for thin films of the granular superconductor NbN. We occasionally see regions with smaller best-fit gaps that correlate with surface topographical features, but have been unable so far to image flux vortices. © 1988, American Vacuum Society. All rights reserved.