Large Fermi surface expansion through anisotropic mixing of conduction and f electrons in the semimetallic Kondo lattice CeBi
Large Fermi surface expansion through anisotropic mixing of conduction and f electrons in the semimetallic Kondo lattice CeBi
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通过半金属 Kondo 晶格 CeBi 中传导和 f 电子的各向异性混合实现大费米面膨胀
DOI：
10.1103/physrevb.100.155110
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发表时间：
2019
影响因子：
3.7
通讯作者：
Liu Yang
中科院分区：
文献类型：
--
作者：
Li Peng;Wu Zhongzheng;Wu Fan;Guo Chunyu;Liu Yi;Liu Haijiang;Sun Zhe;Shi Ming;Rodolakis Fanny;McChesney Jessica L;Cao Chao;Yuan Huiqiu;Steglich Frank;Liu Yang
利用角分辨光电子能谱(ARPES)和共振光电子能谱(ARPES)，我们观察到CeBI在低温下大量膨胀的Ceocket，证明了CeBi中存在着强烈的各向异性导电-电子混合(混合)，而双带没有变化。各向异性费米面(FS)展开伴随着显著的光谱重量从Ce的局域峰(对应于)转移到费米能级附近的巡回导带。仔细的分析表明，观察到的大的FS变化(电子口袋的体积膨胀高达40%)最自然地可以用Ce的小价态变化来解释，这与非常弱的Kondo屏蔽共存。因此，我们的工作提供了由近藤极限深处的真实电荷涨落驱动的FS变化的证据，这高度依赖于轨道性质和动量，并由低载流子密度使其成为可能。
Using angle-resolved photoemission spectroscopy (ARPES) and resonant ARPES, we report evidence of strong anisotropic conduction-electron mixing (mixing) in CeBi by observing a largely expanded Cepocket at low temperature, with no change in the Bibands. The anisotropic Fermi surface (FS) expansion is accompanied by a pronounced spectral weight transfer from the localpeak of Ce (corresponding to) to the itinerant conduction bands near the Fermi level. Careful analysis suggests that the observed large FS change (with a volume expansion of the electron pocket up to 40%) can most naturally be explained by a small valence changeof Ce, which coexists with a very weak Kondo screening. Our work therefore provides evidence for a FS change driven by real charge fluctuations deep in the Kondo limit, which is highly dependent on the orbital character and momentum and is made possible by the low carrier density.