High temperature scanning tunneling microscopy of purely ion conducting yttria stabilized zirconia (YSZ)

Scanning tunneling microscopy (STM) on wide band gap insulators is generally not possible. Here we demonstrate that ionic insulators with high ion mobility, such as yttria stabilized zirconia, are an exception to this rule. The ion conductivity ensures that the sample maintains a defined potential relative to the STM tip and thus a stable tunnel junction. Consequently, ion conductors provide an opportunity for characterizing wide band gap insulators, and thin films and nanostructures supported on them by STM.