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arXiv · 1406.0911

Relationship between single-particle excitation and spin excitation at the Mott Transition

Masanori Kohno
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Abstract

An intuitive interpretation of the relationship between the dispersion relation of the single-particle excitation in a metal and that of the spin excitation in a Mott insulator is presented, based on the results for the one- and two-dimensional Hubbard models obtained by using the Bethe ansatz, dynamical density-matrix renormalization group method, and cluster perturbation theory. The dispersion relation of the spin excitation in the Mott insulator is naturally constructed from that of the single-particle excitation in the zero-doping limit in both one- and two-dimensional Hubbard models, which allows us to interpret the doping-induced states as the states that lose charge character toward the Mott transition. The characteristic feature of the Mott transition is contrasted with the feature of a Fermi liquid and that of the transition between a band insulator and a metal.

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Masanori Kohno. 2014-06-04. Relationship between single-particle excitation and spin excitation at the Mott Transition. https://doi.org/10.7566/jpscp.3.013020

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