Document Type : Research
Authors
1 Payame Noor University
2 Physics Department, Faculty of Science, Payame Noor University, Tehran, Iran
3 Department of Physics, Payame Noor University, Tehran, Iran.
Abstract
A B S T R A C T
This paper investigates the structure of Josephson junctions, which, as one of the most fundamental elements in superconductivity, play a key role in advancement of condensed matter physics, quantum field theory, and modern quantum technologies. The governing equation for the phase of such a system in the absence of dissipation and dispersion is the ordinary sine-Gordon equation, which describes fluxon propagation without considering the effects of dissipation and dispersion. However, in real physical system, the constituent materials of Josephson junctions are always accompanied by dissipation and dispersion, which can significantly affect the dynamical behavior of fluxons. Here, by generalizing the sine-Gordon equation and also considering the control by parameters, the dynamics of fluxons in Josephson junctions have been studied. The result of this study show that the effects of dissipation and dispersion, especially in the presence of a normalized bias current, play a decisive role in the stability, propagation velocity of fluxons. The findings of this research confirm that considering dissipation and dispersion coefficients is essential and cannot be neglected in most cases. According to the calculations and simulations performed, it is observed that the effect of loss and dispersion can be compensated with the help of bias current. Therefore, the studies presented in this paper can be considered an effective step towards more realistic simulation of fluxon dynamics in practical superconducting system.
Keywords
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