Self-heating hotspot effects in HTS thin films

The current-voltage (I-V) characteristics associated with self-heating hotspots in HTS thin films patterned into several different geometries have been investigated under both current-biased and voltage-biased conditions. The hysteretic behavior of the I-V characteristics as a function of sample temperature are in agreement with behavior predicted by resistive hotspot models for superconducting bridges. Additionally, the effect of magnetic fields on the current required to generate, as well as maintain, a normal hotspot has been investigated. Finally, the characteristics of voltage pulses resulting from a step increase in current have been examined to study the propagation of hot spots in HTS films.<<ETX>>