Article

Mechanism of the reorientation of stripes in the cuprates

Physica C Superconductivity (Impact Factor: 0.72). 09/2006; 460. DOI: 10.1016/j.physc.2007.03.266
Source: arXiv

ABSTRACT Using the mean field theory in the slave-boson approach we analyzed the
electron correlation effects in the stripe phases. One finds that a finite
next-nearest neighbor hopping $t'$ plays an important role in the low doping
regime, where it controls the crossover from the filled diagonal to half-filled
vertical/horizontal stripes at doping $ x\simeq 1/16$.

0 Bookmarks
 · 
50 Views
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Using a rotationally invariant version of the slave-boson approach in spin space we analyze the stability of stripe phases with large unit cells in the two-dimensional Hubbard model. This approach allows one to treat strong electron correlations in the stripe phases relevant in the low doping regime, and gives results representative of the thermodynamic limit. Thereby we resolve the longstanding controversy concerning the role played by the kinetic energy in stripe phases. While the transverse hopping across the domain walls yields the largest kinetic energy gain in the case of the insulating stripes with one hole per site, the holes propagating along the domain walls stabilize the metallic vertical stripes with one hole per two sites, as observed in the cuprates. We also show that a finite next-nearest neighbor hopping $t'$ can tip the energy balance between the filled diagonal and half-filled vertical stripes, which might explain a change in the spatial orientation of stripes observed in the high $T_c$ cuprates at the doping $x\simeq 1/16$.
    Physical review. B, Condensed matter 06/2006; · 3.77 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: We propose a new functional integral representation of the Hubbard and Anderson models of lattice fermions. The simplest saddle-point approximation leads, at zero temperature, to the results derived from the Gutzwiller variational wave function. This approach uncovers the limitations of the Gutzwiller approximation and clarifies its connection to the ``slave boson'' mean-field theory of the Anderson model. This formulation leads to the novel strong-coupling mean-field theory which allows for a unified treatment of antiferromagnetism and ferromagnetism, metal-to-insulator transition, and Kondo compensation effects.
    Physical Review Letters 10/1986; 57(11):1362-1365. · 7.73 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Based on an unrestricted Gutzwiller approximation (GA) we investigate the stripe orientation and periodicity in an extended one-band Hubbard model. A negative ratio between next-nearest and nearest neighbor hopping t'/t, as appropriate for cuprates, favors partially filled (metallic) stripes for both vertical and diagonal configurations. At around optimal doping diagonal stripes, site centered (SC) and bond centered (BC) vertical stripes become degenerate suggesting strong lateral and orientational fluctuations. We find that within the GA the resulting phase diagram is in agreement with experiment whereas it is not in the Hartree-Fock approximation due to a strong overestimation of the stripe filling. Results are in agreement with previous calculations within the three-band Hubbard model but with the role of SC and BC stripes interchanged.
    Physical Review B 08/2003; · 3.66 Impact Factor

Full-text (2 Sources)

View
27 Downloads
Available from
Jun 1, 2014