Inductive Shunt Eliminates Thermal Bistability in Superconducting Weak Links.

The quantum phase-coherent behavior of superconducting weak link (WL) is often masked by the heat dissipation and related thermal hysteresis. The latter can be reduced by improving heat evacuation and reducing the critical current, so that a phase-dynamic regime is obtained; however over a narrow bias-current and temperature range. Here we demonstrate that an inductive shunt with well-chosen shunt parameters introduces an unusual nonlinear dynamics that destabilizes an otherwise stable fixed point in the dissipative branch. This leads to a nonhysteretic behavior with large voltage oscillations in intrinsically hysteretic WL-based micron-size superconducting quantum interference devices. A dynamic thermal model describes quantitatively our observations and further allows us to elaborate on the optimal shunting conditions.