RF responses of intrinsic Josephson junction stacks in the flux-flow state have been studied to explore vortex motion. We have reported various RF induced effects on flux-flow of Bi2Sr2CaCu2O 8+y intrinsic Josephson junctions. In a pinning free state, a remarkable zero-crossing step appears at a certain voltage on I-V curve, which is closed to the voltage V = NΦ0f, where N is the number of junction, Φ0 is the flux quantum, f is the RF frequency, respectively. It is shown that vortex motion phase-locked to external microwaves play an important role in the responses. In this report, we have carried out numerical simulation by using the coupled sine-Gordon equations in order to compare with the experimental results. The numerical simulations reveal that the alternating magnetic field of microwaves drives vortices into the stack and generates the zero-crossing step.
- Josephson junction
- Sine-Gordon equation
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics
- Energy Engineering and Power Technology
- Electrical and Electronic Engineering