A Device for Measuring High-TC Superconductor Transition Temperature with Electric Transport and AC Susceptibility Methods Based on Small Cryocooler Cooling
A device for measuring high-TC superconducting transition temperature in a small cryocooler is described which allows a samples temperature to fall steadily from room temperature to 45K.This cryocooler not only meets the high-TC superconductors measurement requirements,but also yields accurate measurement results under ambient conditions.In this device,two measurement methods for measuring high-TC superconducting transition temperature are applied: the electric transport and the AC susceptibility.The former adopts a four-wire method to eliminate the contact resistance between the leads and the sample.During the measurement process the current reversal method for datum processing is applied to eliminate the thermoelectric voltages;this ensures the repeatability error less than 0.4K in the measurement of the superconducting transition temperature.The AC susceptibility method adopts a lock-in amplifier to provide an AC voltage signal for the primary coil,and then lock-in amplifier is used to measure the electrical signals of the secondary coil according to the AC magnetic susceptibility values.The advantage of this device is that by merely changing the position of the sample in the vacuum chamber,the R-T curve and the χ-T curve of a superconducting sample in the same temperature range can be automatically recorded,which provides reliable data for high-TC superconductor transition curve measurement.
High-TC transition temperature Electric transport method AC susceptibility method
Sansheng Wang Xiaoshuai Ning Xianghua Chu Hua Li
School of Physics and Nuclear Energy Engineering, Beihang University, Beijing 100191, China School of Instrument Science & Opto-Electronics Engineering, Beihang University, Beijing, China
国际会议
the Chinese Materials Congress 2012(2012年中国材料大会(CMC2012))
太原
英文
152-157
2012-07-13（万方平台首次上网日期，不代表论文的发表时间）