TY - JOUR

T1 - Pairing correlation functions in the triangular t-J model

T2 - d-wave and f-wave superconductivity

AU - Koretsune, Takashi

AU - Ogata, Masao

PY - 2005/10/1

Y1 - 2005/10/1

N2 - Equal-time pairing correlation functions of the two-dimensional t-J model on the triangular lattice are studied using high-temperature expansions method. We calculate the pairing correlation lengths and the effective pairing interactions down to T∼0.2t, and find the growth of pairing correlations. When t>0 with hole doping, a rapid growth of effective d-wave pairing interaction is found that indicates the resonating-valence-bond superconductivity. In contrast, when t<0, where the ferromagnetic correlation and antiferromagnetic correlation compete, correlation lengths of triplet pairings as well as d-wave pairing grow at low temperatures, although they do not diverge for T→0 in the competing region, i.e., near half-filling. On the other hand, around n=0.4, f-wave pairing correlation tends to diverge, although its effective interaction is small. Relation of the present study to the recently discovered superconductor, NaxCoO2yH2O, is discussed.

AB - Equal-time pairing correlation functions of the two-dimensional t-J model on the triangular lattice are studied using high-temperature expansions method. We calculate the pairing correlation lengths and the effective pairing interactions down to T∼0.2t, and find the growth of pairing correlations. When t>0 with hole doping, a rapid growth of effective d-wave pairing interaction is found that indicates the resonating-valence-bond superconductivity. In contrast, when t<0, where the ferromagnetic correlation and antiferromagnetic correlation compete, correlation lengths of triplet pairings as well as d-wave pairing grow at low temperatures, although they do not diverge for T→0 in the competing region, i.e., near half-filling. On the other hand, around n=0.4, f-wave pairing correlation tends to diverge, although its effective interaction is small. Relation of the present study to the recently discovered superconductor, NaxCoO2yH2O, is discussed.

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U2 - 10.1103/PhysRevB.72.134513

DO - 10.1103/PhysRevB.72.134513

M3 - Article

AN - SCOPUS:29744462934

SN - 1098-0121

VL - 72

JO - Physical Review B - Condensed Matter and Materials Physics

JF - Physical Review B - Condensed Matter and Materials Physics

IS - 13

M1 - 134513

ER -