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.
基金
国家自然科学基金
关键词
稀磁半导体
磁化率
测量
磁相图
Applications
Crystals
Magnetic semiconductors
Magnetization
Magnetometers
Performance
