Photoemission study of the electronic structure and charge density waves of Na2Ti2Sb2O

S. Y. Tan; J. Jiang; Z. R. Ye; X. H. Niu; Y. Song; C. L. Zhang; P. C. Dai; B. P. Xie; X. C. Lai; D. L. Feng

doi:10.1038/srep09515

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arXiv · 1505.01915

Photoemission study of the electronic structure and charge density waves of Na2Ti2Sb2O

S. Y. Tan·J. Jiang·Z. R. Ye·X. H. Niu·Y. Song·C. L. Zhang·P. C. Dai·B. P. Xie·X. C. Lai·D. L. Feng

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Abstract

The electronic structure of Na2Ti2Sb2O, a parent compound of the newly discovered titanium-based oxypnictide superconductors, is studied by photon energy and polarization dependent angle-resolved photoemission spectroscopy (ARPES). The obtained band structure and Fermi surface agree well with the band structure calculation of Na2Ti2Sb2O in the non-magnetic state, which indicating that there is no magnetic order in Na2Ti2Sb2O and the electronic correlation is weak. Polarization dependent ARPES results suggest the multi-band and multi-orbital nature of Na2Ti2Sb2O. Photon energy dependent ARPES results suggest that the electronic structure of Na2Ti2Sb2O is rather two-dimensional. Moreover, we find a density wave energy gap forms below the transition temperature and reaches 65 meV at 7 K, indicating that Na2Ti2Sb2O is likely a weakly correlated CDW material in the strong electron-phonon interaction regime.

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S. Y. Tan, J. Jiang, Z. R. Ye, X. H. Niu, Y. Song, C. L. Zhang, P. C. Dai, B. P. Xie, X. C. Lai, D. L. Feng. 2015-05-08. Photoemission study of the electronic structure and charge density waves of Na2Ti2Sb2O. https://doi.org/10.1038/srep09515

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