一种通过外加直流磁场下交流磁化率测量超导体零场冻结磁通的方法

A Method of Measuring Zero Field Frozen Magnetic Flux of Supercondutor by A.C.Susceptibility Under External Direct Magnetic Field

本文提出一种通过测量外加直流磁场下交流磁化率来研究超导体零场冻结磁通的方法。按外加直流磁场方式不同，测量方法可分为先加场方式（迈斯纳效应）和后加场方式（磁屏蔽过程）两种。对测量方法进行了简要分析。作为应用实例，给出了对Ｂｉ－ｐｂ－Ｓｒ－Ｃｕ－Ｃａ－Ｏ系高温氧化物超导体零场冻结磁通的测量结果。

Abstract A method.by measuring a. c. susceptibility of a sample under externaldirect magnetic field. has been presented for studing zero-field frozen flux in the supercon-ductor.This rneasurement can be done when a sample is entering into superconducting statefrom normal state either befor or after the external field is applied.In other words.eitherthe sample is in a Meissener state or in a state of magnetic shielding.As a example. some ex-perimental results of Bi- pb- Sr- Cu- Ca-O system high temperature superconductor are alsodisscussed in this paper.