稀磁半导体Cd_(1-x)Mn_xS磁化率的研究  

Magnetic Susceptibility of Diluted Magnetic Semiconductor Cd_(1-x)Mn_xS

作　　者：陈辰嘉[1] 瞿明[1] 胡巍 张昕 马可军[2] W.Giriat 

机构地区：[1]北京大学物理系,北京100871 [2]中国科学院上海技术物理研究所,上海200081 [3]Centro de Fisica,Instituto Venezolano de Investigaciones Cientificas,Caracas 1020A,Venezuela

出　　处：《Journal of Semiconductors》1992年第8期457-462,共6页半导体学报（英文版）

基　　金：国家自然科学基金

摘　　要：用振动样品磁强计和提拉法在1.5K≤T≤300K温度范围内系统测量了组分为0.03≤x≤0.45的Cd_(1-x)Mn_xS稀磁半导体单晶样品的磁化率.磁化率测量表明在高温区服从居里-外斯定律。从定量分析得到Mn^(++)离子间交换积分常数值.低场磁化率与温度变化规律(最低温度达1.5K)表明当样品x≤0.2时,体系仍然为顺磁态;而当样品组分x=0.3时,经零场冷却后磁化率在温度T_f处观测到一个尖峰,对x>0.3样品亦得到类似结果,只是磁化率在不同冻结温度T_f处对应一个较宽的峰。这些结果说明在低温区发生从顺磁态到自旋玻璃态的相变.文中给出Cd_(1-x)Mn_sS的磁相图并对此作了讨论.We have measured the magnetic susceptibility for Cd_(1-x)Mn_xS crystals with 0.03≤x≤0.45 in the temperature range of 1.5K≤T≤300K by using a vibrating-sample magnetometer and the extraction method. The susceptibility displays a high-temperature Curie-Weiss behavior. Fromquantitative analysis we obtained the value of the exchange integral constant. Low field magn-etic susceptibility as a function of temperature down to 1.5K shows that the samples with x≤ 0.2remain paramagnetic. Above x=0.3, a cusp after zero-field cooling has been observed at a temperature T_f. The susceptibility has a broad maximum at different freezing temperature T_f withx>0.3 which shows a spin-glass transition in the low temperature range. The magnetic phasediagram for Cd_(1-x) Mn_xS is obtained and discussed.

关 键 词：稀磁半导体 磁化率 测量 磁相图 

分 类 号：TN304.707[电子电信—物理电子学]