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Spectral Function in Mott Insulating Surfaces

L. O. Manuel·C. J. Gazza·A. E. Feiguin·A. E. Trumper
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Abstract

We show theoretically the fingerprints of short-range spiral magnetic correlations in the photoemission spectra of the Mott insulating ground states realized in the triangular silicon surfaces K/Si(111)-B and SiC(0001). The calculated spectra present low energy features of magnetic origin with a reduced dispersion ~10-40 meV compared with the center-of-mass spectra bandwidth ~0.2-0:3 eV. Remarkably, we find that the quasiparticle signal survives only around the magnetic Goldstone modes. Our findings would position these silicon surfaces as new candidates to investigate non-conventional quasiparticle excitations.

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L. O. Manuel, C. J. Gazza, A. E. Feiguin, A. E. Trumper. 2003-03-21. Spectral Function in Mott Insulating Surfaces. https://doi.org/10.1088/0953-8984%2F15%2F17%2F301

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