摘要
在０．３－４．２Ｋ温度范围，测量了ｎ－Ｈｇ１－ｘＣｄｘＴｅ（ｘ＝０．１９５）在磁量子极限后的横向磁阻、纵向磁阻和霍尔系数．观察到了磁致金属－绝缘体相变和相变发生前的霍尔系数下凹＂ＨａｌｌｄｉＰ＂．基于电子在浅施主杂质态上磁冻结的模型，讨论了磁致金属－绝缘体相变的机理及其温度效应和＂Ｈａｌｌｄｉｐ＂的起因．
Abstract Magnetotransport measurements on n-Hg1-xCdxTe(x=0. 195) at low temperatures ranging from 0. 3K to 4.2K and high magnetic field up to 7T are reported.Magneticfield-induced metal-insulator transition(MIT)and anomalous 'Hall dip' before the transition have been observed.Using the model of magnetic freeze-out on shallow donor impurities,we have discussed the mechanism of the magnetic-induced MIT and its temperature effect.The origin of the 'Hall dip' has also been analysed.
关键词
MIT
施主杂质态
半导体
能带结构
HGCDTE
Magnetoelectric effects
Phase transitions
Semiconducting tellurium compounds
