Non-ideal Type II超電導体の磁化過程とA. C. 損失
1966 年 35 巻 1 号 p. 2-14
詳細
1966 年 35 巻 1 号 p. 2-14
High-field superconducting materials such as Nb-(25%) Zr and Nb3Sn have prompted the ex-ploration of applications, including superconducting magnets, energy storage and production of homogeneous fields. These high-field superconductors belong to non-ideal Type II superconductors, which exhibit irreversible magnetic behavior and sustain high critical current density. The major disappointment has been the poor ac characteristics. In this report the magnetization process and the influence of external current on it are explained with a model based on the GLAG theory. The model makes it clear that the hysteresis of magnetization and high-current carrying capacity are caused by the pinning effect of crystal lattice imperfections on the quantized flux line in the mixed state. Next theexperimental results of ac properties are surveyed. It is shown that a model proposed by H. London has revealed the hysteresis mechanism of ac loss and explainsthe experimental data quantitatively.
