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Spectroscopic fingerprints of a surface Mott-Hubbard insulator: the case of SiC(0001)

G. Santoro·S. Scandolo·E. Tosatti
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Abstract

We discuss the spectroscopic fingerprints that a surface Mott-Hubbard insulator should show at the intra-atomic level. The test case considered is that of the Si-terminated SiC(0001) sqrt{3}xsqrt{3} surface, which is known experimentally to be insulating. We argue that, due to the Mott-Hubbard phenomenon, spin unpaired electrons in the Si adatom dangling bonds are expected to give rise to a Si-2p core level spectrum with a characteristic three-peaked structure, as seen experimentally. This structure results from the joint effect of intra-atomic exchange, spatial anisotropy, and spin-orbit coupling. Auger intensities are also discussed.

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G. Santoro, S. Scandolo, E. Tosatti. 2000-06-16. Spectroscopic fingerprints of a surface Mott-Hubbard insulator: the case of SiC(0001). https://doi.org/10.1016/s0039-6028(00)00236-3

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