Nonlinear physics of Josephson tunneling

• Main Authors: Leong, Pui Chan, 梁沛津
• Other Authors: C.D.Hu
• Format: Others
• Language: en_US
• Published: 1998
• Online Access: http://ndltd.ncl.edu.tw/handle/43287415738813687391

碩士 === 國立臺灣大學 === 物理學系 === 86 === Josephson tunneling in superconductors can be described by RCSJ model. In this thesis, we give a deep ananlysis of RCSJ model. We describe the model as a dynamical system, find out the fixed points and calculate the bifurcation curves by Melnikov's method and the Average Theorem. We also derive the theoretical I-V curve. The analysis of the system leads to an analytical solution to the model. The stability of each solution curve is governed by the variational equation. The solution gives a quantitative understanding of the I-V curve. At finite temperature, we add a white noise term to the model. The noise is described by a random process. The cooperative effect of noise and applied a.c. field can excite the system and induce the so-called Stochastic Resonance. We calculate the autocorrelation function and power spectrum by numerical method and also by perturbation. We compare the above wih the noiseless case. We analysis the power spectrum and found the condition of stochastic resonance.