主要研究了(Pr1-yNdy)2/3Sr1/3MnO3体系多晶样品在低温下的比热反常现象.Pr2/3Sr1/3MnO3在低温下没有比热反常现象,但随着Nd替代Pr,比热反常开始出现,峰值逐渐增加,峰值出现温度逐渐减小;在磁场的作用下,峰值减小,峰值出现温度逐渐增加;经分析,该低温比热反常现象与Schottky效应相关.
Specific heat anomaly in the low-temperature range of polycrystalline samples (Pr1-yNdy)0.67Sr0.33MnO3 were studied. At low temperatures,specific heat anomaly is found in Nd2/3Sr1/3MnO3,but not in Pr2/3Sr1/3MnO3 sample. It is found that the peak value of the anomaly increases and the peak temperature decreases as the increase of Nd substitution content for Pr. The peak value of the anomaly decreases and the peak temperature increases under an applied magnetic field. The specific heat anomaly is believed to be related to the Schottky effect.