Striped phases in the two-dimensional Hubbard model with long-range Coulomb interaction

We investigate the formation of partially filled domain walls in the two-di mensional Hubbard model in the presence of a long-range interaction. Using an unrestricted Gutzwiller variational approach we show that (i) the strong local interaction favors charge segregation in stripe domain walls, (ii) t he long-range interaction favors the formation of half-filled vertical stri pes with a period doubling due to the charge and a period quadrupling due t o the spins along the watt. Our results show that, besides the underlying l attice structure, also the electronic interactions can contribute to determ ine the different domain wall textures observed in Nd-doped copper oxides a nd nickel oxides. [S0163-1829(98)03540-1].