缺陷调控临界温度梯度超导膜的磁通整流反转效应  

Tunable reversal rectification in T_(c)-gradient superconducting film by slit

作　　者：何安 薛存 He An;Xue Cun(College of Science,Chang’an University,Xi’an 710064,China;School of Mechanics,Civil Engineering and Architecture,Northwestern Polytechnical University,Xi’an 710072,China)

机构地区：[1]长安大学理学院,西安710064 [2]西北工业大学力学与土木建筑学院,西安710072

出　　处：《物理学报》2022年第2期271-278,共8页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:11702034,11972298,11702218);中央高校基本科研业务费专项资金(批准号:300102121201);中国博士后科学基金(批准号:2019M663812)资助的课题。

摘　　要：超导涡旋运动引起的棘齿效应可以广泛应用于磁通泵、整流器和超导开关等装置.金兹堡-朗道理论是研究超导磁通涡旋问题强有力的工具和手段.本文采用有限差分法数值求解时间相关的金兹堡-朗道方程,利用快速傅里叶变换方法求解耦合的热传导方程,数值模拟了临界温度梯度超导薄膜磁通涡旋动力学行为,提出了一种新的调节超导整流效应的方式,并研究了临界温度梯度大小和缺陷位置对超导整流电压反转现象的影响规律.由于超导边界势垒和缺陷吸引势对磁通涡旋的共同作用,当缺陷位置偏向临界温度较高的一侧或者临界温度梯度较小时有利于观察到整流电压随交流幅值增大发生的反转现象.The ratchet effect caused by superconducting vortex motion can be widely used in flux pumps,rectifiers and superconducting switches.Ginzburg-Landau theory provides a powerful tool to investigate superconducting vortex matter.In this paper,the finite difference method is used to numerically solve the time-dependent Ginzburg-Landau equation,and the fast Fourier transform method is used to solve the coupled heat conduction equation.The vortex dynamic behavior of the superconducting thin film with a linear change of critical temperature is simulated numerically,and a new way to regulate the superconducting rectification effect is proposed.The effect of critical temperature gradient and slit location on the reversal phenomenon of rectified voltage are studied.Because of the influence of edge barrier and the defect attraction potential on vortex motion,it is beneficial to observing the reversal rectified voltage with increasing AC amplitude that the defect location is near to the side of the higher critical temperature or the gradient of the critical temperature is small.

关 键 词：超导薄膜 整流电压 临界温度梯度 缺陷 

分 类 号：O469[理学—凝聚态物理]