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ARPES Study of X-Point Band Overlaps in LaB$_6$ and SmB$_6$ - Contrast to SrB$_6$ and EuB$_6$

S. -K. Mo·G. -H. Gweon·J. D. Denlinger·H. -D. Kim·J. W. Allen·C. G. Olson·H. Höchst·J. L. Sarrao·Z. Fisk
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Abstract

In contrast to our recent finding of an X-point band gap in divalent hexaborides, we report here that angle resolved photoemission spectroscopy (ARPES) data shows that the gap is absent for trivalent LaB$_6$ and is absent or nearly so for mixed valent SmB$_6$. This finding demonstrates a nontrivial evolution of the band structure from divalent to trivalent hexaborides.

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S. -K. Mo, G. -H. Gweon, J. D. Denlinger, H. -D. Kim, J. W. Allen, C. G. Olson, H. Höchst, J. L. Sarrao, Z. Fisk. 2001-07-10. ARPES Study of X-Point Band Overlaps in LaB$_6$ and SmB$_6$ - Contrast to SrB$_6$ and EuB$_6$. https://doi.org/10.1016/s0921-4526(01)01291-1

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