TY - JOUR
T1 - Interplay between antiferromagnetism and superconductivity in two-dimensional Hubbard model
AU - Kobayashi, Kenji
AU - Yokoyama, Hisatoshi
PY - 2008/12/1
Y1 - 2008/12/1
N2 - Using a variational Monte Carlo method, we discuss the interplay between antiferromagnetism (AF) and superconductivity (SC) in a Hubbard model on a square lattice with a diagonal transfer t′. We simultaneously introduce the following improvements into the trial function: (1) coexistence of AF and d-wave singlet gaps that allows a continuous description of their interplay, (2) band renormalization effect in the range of fourth-neighbor hopping, and (3) refined doublon-holon correlation factors. For t′ / t = - 0.3, appropriate to hole-doped cuprates, it is found that AF ordered state is stabilized near half filling, especially, for U ∼ band width, by retrieving the nesting condition. As the doping rate increases, AF is weakened and a pure d-wave SC phase evolves for large U. The coexisting state of SC and AF orders appears only in a narrow range of U (∼ band width) and electron density n (= 0.8).
AB - Using a variational Monte Carlo method, we discuss the interplay between antiferromagnetism (AF) and superconductivity (SC) in a Hubbard model on a square lattice with a diagonal transfer t′. We simultaneously introduce the following improvements into the trial function: (1) coexistence of AF and d-wave singlet gaps that allows a continuous description of their interplay, (2) band renormalization effect in the range of fourth-neighbor hopping, and (3) refined doublon-holon correlation factors. For t′ / t = - 0.3, appropriate to hole-doped cuprates, it is found that AF ordered state is stabilized near half filling, especially, for U ∼ band width, by retrieving the nesting condition. As the doping rate increases, AF is weakened and a pure d-wave SC phase evolves for large U. The coexisting state of SC and AF orders appears only in a narrow range of U (∼ band width) and electron density n (= 0.8).
KW - A. Oxides
KW - D. Electronic structure
KW - D. Fermi surface
KW - D. Magnetic properties
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U2 - 10.1016/j.jpcs.2008.06.065
DO - 10.1016/j.jpcs.2008.06.065
M3 - Article
AN - SCOPUS:57049177518
VL - 69
SP - 3274
EP - 3276
JO - Journal of Physics and Chemistry of Solids
JF - Journal of Physics and Chemistry of Solids
SN - 0022-3697
IS - 12
ER -