中文摘要：

对电脉冲诱导的不同电阻态下La0.7Ca0.3MnO3样品的比热进行了研究.实验结果表明,电脉冲导致La0.7Ca0.3MnO3样品比热随电阻状态发生可逆变化.比热随电阻状态的减小而减小.低温比热拟合及不同电阻状态下的比热差与温度关系说明,声子对比热的贡献不随电阻状态变化,磁性和载流子对比热的贡献是导致La0.7Ca0.3MnO3样品比热变化的原因.电脉冲诱导O离子沿一维扩展性缺陷的电化学迁移,导致材料中局部区域的O离子浓度发生变化.O离子浓度的变化导致载流子浓度的变化,同时载流子浓度的变化将使得低温下磁性耦合强度发生变化,从而导致比热发生变化.

英文摘要：

The specific heat of polycrystalline La0.7Ca0.3 MnO3 at different resistance states induced by electric pulses was studied.It was found that the specific heat decreases with decreasing resistance,and the change is reversible.The reversible change of specific heat was shown to be mainly due to the ferromagnetic-spin-waves component and charge carriers component by fitting the specific heat data.These results indicate that the electric pulses modulated the magnetic configuration of LCMO at low temperature,which would result in large variation in magnetization and specific heat associated with ferromagnetic-spin-waves.