Prediction of half harmonic generation in stacked Josephson junctions and Bi2Sr2CaCu2Ox single crystals

We demonstrate analytically that parametric excitation of certain plasma resonance modes in Bi2Sr2CaCu2Ox single crystals is possible. The model we use is that of a Josephson stack, and the fundamental mechanism is that of half harmonic generation in time and space when a threshold of the applied rf signal is exceeded. The phenomenon is important as a diagnostic tool for the investigation of plasma resonance in Bi2Sr2CaCu2Ox-like materials, as well as being a basis for making high-T-c high-frequency parametric amplifiers. It has same unique features of space and time nonlinear behavior.