Transport properties of pure and doped MNiSn (M=Zr, Hf)
Transport properties of pure and doped MNiSn (M=Zr, Hf)
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DOI：
10.1103/physrevb.59.8615
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发表时间：
1999-04-01
影响因子：
3.7
通讯作者：
Meisner, GP
中科院分区：
文献类型：
--
作者：
Uher, C;Yang, J;Meisner, GP
我们研究了一族杂波掺杂的Mnisi(M=Zr，Hf)金属间化合物的输运性质，这种结构被称为半-Heusler合金。我们已经证明，这种输运对组成原子的结构排列非常敏感，这可以通过退火、等结构合金化和掺杂来控制。这种不同寻常的输运性质是在纯合金中近150K的半金属-半导体转变的背景下被观察到的，掺入铟可以使转变向上移动到200K。高温输运是由重电子的存在主导的，这导致了令人惊讶的大热电势。微量的Sb(NL型掺杂)对输运性质有惊人的影响，并使其在所有温度下的电阻率和霍尔效应都像金属一样。Sb掺杂合金表现出非常高的热电功率因数，但其导热系数仍然太高，不足以使其成为一种有前途的热电材料。[S0163-1829(99)07013-7]。
We have studied the transport properties in a family of purr and doped intermetallics of the form MNiSi (M=Zr, Hf), the structures known as the half-Heusler alloys. We have shown that the transport is very sensitive to structural arrangements of the constituent atoms, and this can be manipulated by annealing, isostructural alloying, and doping. The unusual transport properties are viewed in the context of a semimetal-semiconductor transition that in pure alloys sets in near 150 K. Doping with indium can shift the transition upward towards 200 K. The high-temperature transport is dominated by the presence of heavy electrons that are responsible for surprisingly large values of thermopower. Minute amount of antimony (nl-type doping) have a spectacular influence on the nature of transport and drive the electrical resistivity and Hall effect to be metal-like at all temperatures. Sb-doped alloys display very high thermoelectric power factors, but the thermal conductivity is still too high to make the material a prospective thermoelectric. [S0163-1829(99)07013-7].