通过电阻率-温度(temperature dependence of resistivity,ρ-T)曲线、磁化强度-温度(temperature dependence of magnetization ,M-T)曲线、ESR谱线的测量,研究了La0.45Ca0.55MnO3样品的电磁特性.结果表明,样品在整个测量温区呈现绝缘体行为,输运机制满足可变程跃迁模型.样品存在电荷有序(charge ordering,CO)相,相变温度TCO≈240K,并随温度降低发生顺磁(paramagnetism,PM)→电荷有序(CO)→反铁磁(antiferromagnetism,AFM)变化.值得注意的是,由于样品低温下存在多种复杂的磁相互作用,在40K发生自旋玻璃转变,表现为再入型自旋玻璃行为.
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