期刊论文详细信息
Entropy
Maximum Entropy Distributions Describing Critical Currents in Superconductors
关键词: superconductor;    maximum entropy;    critical current;   
DOI  :  10.3390/e15072585
来源: mdpi
PDF
【 摘 要 】

Maximum entropy inference can be used to find equations for the critical currents (Jc) in a type II superconductor as a function of temperature, applied magnetic field, and angle of the applied field, θ or ϕ. This approach provides an understanding of how the macroscopic critical currents arise from averaging over different sources of vortex pinning. The dependence of critical currents on temperature and magnetic field can be derived with logarithmic constraints and accord with expressions which have been widely used with empirical justification since the first development of technical superconductors. In this paper we provide a physical interpretation of the constraints leading to the distributions for Jc(T) and Jc(B), and discuss the implications for experimental data analysis. We expand the maximum entropy analysis of angular Jc data to encompass samples which have correlated defects at arbitrary angles to the crystal axes giving both symmetric and asymmetric peaks and samples which show vortex channeling behavior. The distributions for angular data are derived using combinations of first, second or fourth order constraints on cot θ or cot ϕ. We discuss why these distributions apply whether or not correlated defects are aligned with the crystal axes and thereby provide a unified description of critical currents in superconductors. For J//B we discuss what the maximum entropy equations imply about the vortex geometry.

【 授权许可】

CC BY   
© 2013 by the authors; licensee MDPI, Basel, Switzerland.

【 预 览 】
附件列表
Files Size Format View
RO202003190035385ZK.pdf 563KB PDF download
  文献评价指标  
  下载次数:23次 浏览次数:22次