Fine structure of voltage levels in the I-V characteristics of the rf SQUID’s

Abstract
Results of digital numerical calculations of the rf-(SQUID) superconducting quantum interference device dynamics and I-V characteristics are presented. Fine structure of voltage levels in the I-V characteristics were found. We have introduced thermal noise effects via Langevin term in the equations of motion. The thermal noise causes transitions between the voltage levels. In the case of a SQUID with an underdamped junction, negative slope can be observed, which is due to to the transition to the lower voltage levels.