This paper discusses biomagnetic effects and their possible applications that are unfamiliar to cryogenic and superconducting engineers. Biomagnetism is exotic applied magnetics and a transdisciplinary research target. There are two types of research methodology, physical and epidemiological. They are quite different. Both methodologies should be harmonized. The author proposes how to work in this transdisciplinary field. Finally, suggestions of guidelines for studing exotic phenomena are presented.
The cylindrical bulk current lead was fabricated using Pb-free Bi system superconductors in a solid-state reaction. The current lead attained a high transport critical-current density (Jc) of about 320A/cm2 at 77K, 0T and more than 1, 200A/cm2 at 40K, 2T. The Pb-free current lead was composed of both Bi-2223 and Bi-2212 phases judging from the AC susceptibility curve and X-ray diffraction pattern. The heat leakage and mechanical strength of the Pb-free cylindrical bulk current lead were approximately similar to those of a Pb-dope current lead consisting of the Bi-2223 phase only. The Pb-free bulk lead particularly showed a high Jc property at low temperatures and high magnetic field. The Pb-free current lead had the characteristics of both Bi-2212 and Bi-2223 phases. The application of the bulk current lead for a cryocooled superconducting magnet was investigated.