Electronic-structure-driven magnetic ordering in a Kondo semiconductor CeOs2Al10.
Electronic-structure-driven magnetic ordering in a Kondo semiconductor CeOs2Al10.
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DOI：
10.1103/physrevlett.106.056404
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发表时间：
2010-05
影响因子：
8.6
通讯作者：
S. Kimura;T. Iizuka;H. Miyazaki;A. Irizawa;Y. Muro;T. Takabatake
中科院分区：
文献类型：
--
作者：
S. Kimura;T. Iizuka;H. Miyazaki;A. Irizawa;Y. Muro;T. Takabatake
本文报道了近藤半导体CeOs（2）Al（10）在反铁磁有序温度T（0）为29 K时电子结构的各向异性变化。沿a轴和c轴沿着的光谱表明，由于导带和近局域4f态之间的杂化而产生的能隙，即c-f杂化能隙，在T（0）上从更高的温度连续出现。另一方面，沿着B轴，在39 K（>T（0））处具有20 meV峰值的另一能隙变得可见，并且由于电荷不稳定性而在T（0）处完全打开。这一结果表明，能隙的出现，以及沿着B轴的电子结构的变化，诱导反铁磁有序低于T（0）。
We report the anisotropic changes in the electronic structure of a Kondo semiconductor CeOs(2)Al(10) across an anomalous antiferromagnetic ordering temperature (T(0)) of 29 K, using optical conductivity spectra. The spectra along the a and c axes indicate that an energy gap due to the hybridization between conduction bands and nearly local 4f states, namely the c-f hybridization gap, emerges from a higher temperature continuously across T(0). Along the b axis, on the other hand, another energy gap with a peak at 20 meV becomes visible at 39 K (>T(0)) and fully opens at T(0) because of a charge instability. This result implies that the appearance of the energy gap, as well as the change in the electronic structure along the b axis, induces the antiferromagnetic ordering below T(0).