Direct observation of rectification effect of quantized magnetic flux

本研究的目的是揭示超导薄膜中量子化磁通的行为与磁通整流效应的关系。晶界是氧化物超导薄膜的薄弱环节。本研究利用超导量子干涉仪显微镜（SSM）对超导薄膜中的磁通子进行了观测。通过使用SSM，磁通子可以被一个一个地观察到。在此基础上，建立了超导薄膜针尖电流的测量方法。通过对针尖电流矢量的监测，可以研究薄膜中磁通子的行为。研究了基于准平衡的Bi系超导薄膜的制备。

The objective of this study is to reveal the behavior of the quantized flux(fluxon) in superconducting thin films with respect to fluxon rectification effect. Grain boundary in an oxide superconducting thin film works as a weak link. In this study, fluxons in superconducting thin films were observed by scanning SQUID(superconducting quantum interference device) microscopy(SSM). By using SSM, fluxons can be observed one by one. Further, measurement of method of pin-point current flow in a superconducting film by using SSM was established. Behavior of fluxons in films can be investigated with pin-point current vector monitored. Fabrication of thin films of Bi-based superconductor based on quasi-equilibrium was also investigated.