脈沖強磁場下電輸運和磁測量系統(tǒng)及其(la,1xbi,x),0.67ca,0.33mno,3體系磁特性研究

1、華中科技大學碩士學位論文脈沖強磁場下電輸運和磁測量系統(tǒng)及其（LaBi）CaMnO體系磁特性研究姓名：李海娜申請學位級別：碩士專業(yè)：材料物理與化學指導教師：夏正才20090501II 華 中 科 技 大 學 碩 士 學 位 論 文 Abstract In this paper, the science and technology of the pulsed high magnetic field are in

2、troduced. Based on the pulsed high magnetic field and low temperature system, we desigened the magnetization measurement and electrical transport measurement holders. At the same time, a digital

3、 filter was developed to deal with this measuring noise problem..Using the designed system, the magnetization characteristics of (La1- xBix)0.67Ca0.33MnO3 was measured. The thesis mainly contains following

4、 contents: First of all, an overview of the science and technology of pulsed high magnetic field and the base structure of pulsed high magnetic field was described. Secondly, the basic theory

5、 on magnetization measurements and electrical transport measurements were systematic introduced. At the same time, because there are a lot of high- frequency noises mixed into the signals due to

6、 the outside interference in the process of signal transmission, a new digital filter was developed. Thirdly, the crystal structure of vanadium and the corresponding properties were studied, inclu

7、ding the metal- insulator transition、 spin induced G- type to C- type transition and so on. Finally, the magnetic properties of (La1- xBix)0.67Ca0.33MnO3 was measured, the saturated magnetization was

8、 changed with magnetic field in different doping level and different temperature, an obvious hysteresis phenomenon was observed in the manganites with higher doping level. Keywords: Pulsed high magnetic f