共振受主态在零禁带Hg_(1-x)Mn_xTe磁量子输运中的影响  

RESONANT ACCEPTOR INFLUENCED QUANTUM TRANSPORT BEHAVIOR OF ZERO-GAP P-Hg_(1-x)Mn_xTe

作　　者：沈金熙[1] 郑国珍[1] 郭少令[1] 汤定元[1] 马可军[1] 

机构地区：[1]中国科学院上海技术物理研究所红外物理国家实验室,上海200083

出　　处：《红外与毫米波学报》1992年第2期109-116,共8页Journal of Infrared and Millimeter Waves

摘　　要：在温度为0.3～4.2K,磁场强度为0～7T的范围内对两个不同组份的Hg_(1-x)Mn_xTe(N_A>N_D)样品进行了输运特性的研究.组份x=0.03的样品在弱磁场(B<0.6T)下出现磁阻振荡,用修正的Pidgeon-Brown模型拟合各振荡峰值位置,得到共振受主能级随温度降低而升高,表明受主共振态已形成束缚磁极化子(RABMP).组份x=0.065的样品出现阶段性下降负磁阻行为,理论分析表明这是受主能级钉扎费密能级并在强场(B～1.5T)通过a_v(-1)价带顶引起价带空穴散射增强.两个样品都呈现负磁阻行为,但从磁阻的各向异性及能带分析表明其机理有所不同.Transport behaviors of two samples of zero-gap P-Hg_(1-x)Mn_xTe (N_A>N_D)have been carefully studied at temperatures 0.3～4.2K and magnetic fields 0～7T. For thesample with x=0.03, Resonant-Acceptor-Bound Magnetic Polarons (RABMP) havebeen found by means of Shubnikov de Haas oscillation. The oscillation peaks have been fit-ted by detailed calculations of the modified Pidgeon-Brown model. The resonant acceptorenergy (which pins the Fermi level) increases with decreasing temperatures, which is the fea-ture of RABMP′s. For the sample with x=0.065, the two-stage negative magnetoresist-ance (NMR) has been found at extremely low temperatures, associated with the Fermi levelpassing through the valence band α_v (-1). All the samples showed NMR, but their mecha-nisms are quite different.

关 键 词：共振受主态 零禁带 碲锰汞 

分 类 号：TN304.26[电子电信—物理电子学]