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arXiv · 1712.05490

Competition among various charge-inhomogeneous states and d-wave superconducting state in Hubbard models on square lattices

Kota Ido·Takahiro Ohgoe·Masatoshi Imada
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Abstract

We study competitions between charge uniform and inhomogeneous states in two-dimensional Hubbard models by using a variational Monte Carlo method. At realistic parameters for cuprate superconductors, emergent effective attraction of carriers generated from repulsive Coulomb interaction leads to charge/spin stripe ground states, which severely compete with uniform superconducting excited states in the energy scale of 10 K for the cuprates. Stripe period increases with decreasing hole doping $δ$, which agrees with the experiments for La-based cuprates at $δ$ = 1/8. For lower $δ$, we find a phase separation. Implications of the emergent attraction for the cuprates are discussed.

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Kota Ido, Takahiro Ohgoe, Masatoshi Imada. 2017-12-19. Competition among various charge-inhomogeneous states and d-wave superconducting state in Hubbard models on square lattices. https://doi.org/10.1103/physrevb.97.045138

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