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Electronic Structure of Mott Insulators Studied by Inelastic X-ray Scattering

M. Z. Hasan·E. D. Isaacs·Z-X. Shen·L. L. Miller·K. Tsutsui·T. Tohyama·S. Maekawa
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Abstract

The electronic structure of Mott insulators continues to be a major unsolved problem in physics despite more than half-century of intense research efforts. Well-developed momentum-resolved spectroscopies such as photoemission or neutron scattering cannot probe the full Mott gap. We report observation of dispersive charge excitations across the Mott gap in a high Tc parent cuprate Ca2CuO2Cl2 using high resolution resonant inelastic x-ray scattering shedding light on the anisotropy of Mott-gap. The results provide direct support for the Hubbard model to describe charge excitations across the Mott gap.

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M. Z. Hasan, E. D. Isaacs, Z-X. Shen, L. L. Miller, K. Tsutsui, T. Tohyama, S. Maekawa. 2001-03-24. Electronic Structure of Mott Insulators Studied by Inelastic X-ray Scattering. https://doi.org/10.1126/science.288.5472.1811

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