Extraordinary Hall effect in La0.7Ca0.3MnO3 and La0.7Ba0.3MnO3 thin films
Extraordinary Hall effect in La0.7Ca0.3MnO3 and La0.7Ba0.3MnO3 thin films
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La0.7Ca0.3MnO3 和 La0.7Ba0.3MnO3 薄膜中非凡的霍尔效应
DOI：
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发表时间：
1999
期刊：
影响因子：
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通讯作者：
C. Srinitiwarawong
中科院分区：
文献类型：
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作者：
M. Ziese;C. Srinitiwarawong
测量了La0.7Ba0.3MnO3和La0.7Ca0.3MnO3薄膜在μ0H≤1 T和温度为10 K≤T≤340 K条件下的霍尔效应。在铁磁相中，零磁感应时霍尔电阻率的斜率随温度的升高而迅速增大，直到居里温度TC达到最大值。霍尔电阻率与磁化强度的详细比较有助于区分普通霍尔效应和特殊霍尔效应。普通霍尔常数RH在TC以下有一个跳跃。非凡的霍尔常数RA与零场电阻率成比例。在低温下，我们发现RA对电阻率的二次依赖关系跨越到高温下的线性依赖关系。虽然铁磁相位的二次标度规律可以用传统的侧跃机制来解释，但在TC附近和跳频区域的线性依赖与传统的斜散射不一致。这些数据与最近关于双交换铁磁体霍尔效应的理论进行了比较。
The Hall effect of La0.7Ba0.3MnO3 and La0.7Ca0.3MnO3 thin films was measured in magnetic fields μ0H ⩽ 1 T and for temperatures 10 K ⩽ T ⩽ 340 K. In the ferromagnetic phase the slope of the Hall resistivity at zero magnetic induction rapidly increases with temperature until a maximum is reached at the Curie temperature TC. A detailed comparison of the Hall resistivity with the magnetization facilitates the separation of the ordinary and extraordinary Hall effect. The ordinary Hall constant RH shows a jump below TC. The extraordinary Hall constant RA scales with the zero-field resistivity. At low temperatures we find a quadratic dependence of RA on the resistivity crossing over to a linear dependence at higher temperatures. Whereas the quadratic scaling law in the ferromagnetic phase can be explained by a conventional side-jump mechanism, the linear dependence near TC and in the hopping regime is inconsistent with conventional skew scattering. The data are compared to a recent theory of the Hall effect in double-exchange ferromagnets.