RF impedance of intrinsic Josephson junction in flux-flow state with a periodic pinning potential

✍ Scribed by Y. Yamada; K. Nakajima; K. Nakajima

• Publisher: Elsevier Science
• Year: 2008
• Tongue: English
• Weight: 235 KB
• Volume: 468
• Category: Article
• ISSN: 0921-4534
• DOI: 10.1016/j.physc.2008.05.014

✦ Synopsis

We have investigated the dynamics of Josephson vortices interacting with electromagnetic waves in Bi 2 Sr 2 CaCu 2 O 8+y intrinsic Josephson junction (IJJ) stacks by means of millimeter wave irradiation and numerical simulations based on coupled sine-Gordon equations while taking into account a sinusoidal form of the periodic pinning potential. The numerical simulation results for the influence of the electromagnetic waves on the flux-flow properties reveal that the periodic pinning potential induces the inphase motion of Josephson vortices over the junctions. In order to prove from another viewpoint, we investigate RF impedance of IJJ in flux-flow state in this study. A remarkable negative real part region appears at 1st harmonic step, it means that the IJJ in flux-flow state acts as an oscillator at the negative real part region.