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Nature of the Peierls- to Mott-insulator transition in 1D

H. Fehske·A. P. Kampf·M. Sekania·G. Wellein
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Abstract

In order to clarify the physics of the crossover from a Peierls band insulator to a correlated Mott-Hubbard insulator, we analyze ground-state and spectral properties of the one-dimensional half-filled Holstein-Hubbard model using quasi-exact numerical techniques. In the adiabatic limit the transition is connected to the band to Mott insulator transition of the ionic Hubbard model. Depending on the strengths of the electron-phonon coupling and the Hubbard interaction the transition is either first order or evolves continuously across an intermediate phase with finite spin, charge, and optical excitation gaps.

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H. Fehske, A. P. Kampf, M. Sekania, G. Wellein. 2002-11-11. Nature of the Peierls- to Mott-insulator transition in 1D. https://doi.org/10.1140/epjb%2Fe2003-00002-2

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