Detection of low-level dissipation and thermal instability in YBa2Cu3O7-delta microbridges using low temperature near-field scanning microwave microscopy

作者：Dizon Jonathan R^*; Lu Rongtao; Wang Xiang; Wu Judy Z

来源：Superconductor Science and Technology, 2010, 23(5): 055001.

DOI：10.1088/0953-2048/23/5/055001

Near-field scanning microwave microscopy (NSMM) was combined with electrical transport measurements to detect the dynamic evolution of low-level dissipation and thermal instability in YBa2Cu3O7-delta microbridges in the superconducting state driven by temperature, applied current and self-heating. High sensitivity NSMM enables quantitative detection of dissipation evolution starting from 3 to 4 orders of magnitude lower than the transport critical current criterion. The nonlinear step-like feature in the dynamic development of dissipation suggests a bi-modal evolution pattern of nucleation of isolated hot spots followed by their spreading/coalescence. A linear behavior prevails near the superconducting-to-normal transition.

• 出版日期2010-5