The Josephson junction is a device and constructed by separating two superconductors with an insulating barrier, which is thin enough so that super-electrons or Cooper pairs, composed of two electrons with opposite momenta and spins, formed by the electron-phonon interaction, and described as probability waves, can quantummechanically tunnel through the barrier and cause superposition and interferences. Due to the quantum e↵ect, a Josephson junction can generate and sustain an indefinitely long direct electric current or potential di↵erence, which becomes alternating one when an external voltage is applied. This paper investigates the Josephson pulse including its generation, property, and control. The results obtained from this study indicate that perturbations of the superconductors can generate strong superconducting pulses in the Josephson junction. The electric potential and field in the barrier oscillate when the two superconductors have di↵erent physical properties including the number densities of super-electrons, the phases of superconductors, and their rates of variations. The oscillations can be harmonic, combined, and purely pulse-like. The strength of the pulse increases with the di↵erences in the rates of densities and phases between the two superconductors. The pulse can be stronger in strength and narrower in width when one superconductor has lower density but higher rates of density and phase than another superconductor. Light or electromagnetic waves can perturb the superconductivities of superconductors and hence can be applied to control the pulses of Josephson junctions.
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