Stimulation of Tunneling by a High-Frequency Field: Decay of the Zero-Voltage State in Josephson Junctions

Abstract

We find the tunneling decay rate $D$ of the zero-voltage states of a Josephson junction driven by a small ac current $I_{1}cos\left(\Omega t\right)$, when the dc current is close to the critical one. In the high-frequency limit $\Omega \gg {\omega }_p$ (${\omega }_p$ is the plasma frequency) for a high-$Q$ junction, the amplitude $I_1$ enters into the tunneling exponent with a large exponential factor and $\ln D\propto I_1\exp \left(\frac{1.77\Omega }{{\omega }_p}\right)$.