Unusual features of erbium-based Heusler phases
Unusual features of erbium-based Heusler phases
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DOI：
10.1016/j.jmmm.2004.11.538
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发表时间：
2005-04-01
影响因子：
2.7
通讯作者：
Grin, Y
中科院分区：
文献类型：
--
作者：
Kaczorowski, D;Gofryk, K;Grin, Y
采用x射线衍射、磁化率、电阻率、热电功率和霍尔效应测量等方法对Heusler合金ErPd2Sb、ErPd2Bi、ErPdSb和ErPdBi进行了研究。由于Er3+离子的局域磁性，所有这些化合物的顺磁性低至1.7 K。它们的电学行为受E-F附近电子能带结构中狭窄间隙的形成所支配。电子和空穴都对电导率有贡献，但p型载流子起主导作用。霍尔响应强烈依赖于油温和外加磁场，从而反映了底层电子结构的复杂性。在室温下，ErPdSb的塞贝克系数约为150 μ V/K，这使得该材料有望成为热电应用的候选者。所有四种化合物的共同特点是电阻率在6-8 K以下迅速下降，这似乎表明磁性或超导起源的相变，尽管在低温磁化率和比热中没有任何相应的异常。(c) 2004 Elsevier B.V.版权所有
Heusler alloys ErPd2Sb, ErPd2Bi, ErPdSb and ErPdBi were studied by means of X-ray diffraction, magnetic susceptibility, electrical resistivity, thermoelectric power and Hall effect measurements. All these compounds are paramagnetic down to 1.7 K due to localized magnetism of Er3+ ions. Their electrical behavior is governed by the formation of narrow gaps in the electronic band structures near E-F. Both electrons and holes contribute to the conductivity, yet the dominant role is played by p-type carriers. The Hall response is strongly dependent oil temperature and applied magnetic field, thus reflecting complex character of the underlying electronic structures. The Seebeck coefficient in ErPdSb is of the order of 150 mu V/K at room temperature making this material promising candidate for thermoelectric applications. Common to all four compounds studied is a rapid drop in the resistivity below 6-8 K that seems manifest a phase transition of magnetic or superconducting origin, despite the lack of any corresponding anomalies in the low-temperature magnetic susceptibility and specific heat. (c) 2004 Elsevier B.V. All rights reserved.