Nonlinear response of Josephson vortex flow in Bi-2212 with pancake vortices

Nonlinear response of Josephson vortex (JV) flow has been studied for controlling the JV motion. Rectification effect has been observed clearly with a biharmonic ac drive in the current–voltage measurements in the presence of pancake vortices. This method has a large advantage in changing the polarity of the rectified voltage with varying the phase- and the frequency-difference, compared to the spatially asymmetric nano-dots/anti-dots. Using a Bi₂Sr₂CaCu₂O_8+y single crystal, multiply-stacked Josephson junctions result us in obtaining a large gain. Further application of this method will be promising.