Stripe orders driven by long-range Coulomb forces in the 2D-Hubbard model

G. Seibold, Claudio Castellani, C. Di Castro +1 more

R. Citro, M. Marinaro

Thomas Maier, Gonzalo A. Álvarez, Michael S. Summers +1 more

Masaru Kato

The extended Hubbard model with the nearest-neighbor Coulomb interaction on the square lattice is studied within the mean-field approximation. The stable states for 8×8 sites lattice with the periodic boundary condition and the electron filling n=0.875, as well as for 10×10 lattice and n=0.80, are obtained. For 8×8 lattice where quarter-filled straight stripe is expected because of the long-range Coulomb interaction, the cross stripe phases become stable.

R. Lemański, James K. Freericks, Grzegorz Banach

The observation of charge stripe order in the doped nickelate and cuprate materials has motivated much theoretical effort to understand the underlying mechanism of the stripe phase. Numerical studies of the Hubbard model show two possibilities: (i) stripe order arises from a tendency toward phase separation and its competition with the long-range Coulomb interaction or (ii) stripe order inherently arises as a compromise between itinerancy and magnetic interactions. Here we determine the restricted phase diagram of the two-dimensional Falicov-Kimball model and see that it displays rich behavior illustrating both possibilities in different regions.

Mingpu Qin, Chia-Min Chung, Hao Shi +2 more