Two-hole problem in the t-J model: A canonical transformation approach

Article

关键词: HIGH-TEMPERATURE SUPERCONDUCTIVITY;    2-HOLE BOUND-STATES;    SPIN-WAVE EXCHANGE;    QUANTUM ANTIFERROMAGNET;    SPECTRAL-FUNCTION;    SPIRAL PHASE;    CUO2 PLANES;    HUBBARD ANTIFERROMAGNET;    DOPED ANTIFERROMAGNET;    OXIDE SUPERCONDUCTORS;   

DOI  :  10.1103/PhysRevB.56.3381

来源: SCIE

【 摘 要 】

The t-J model in the spinless-fermion representation is studied. An effective Hamiltonian for the quasiparticles is derived using a canonical transformation approach. It is shown that the rather simple form of the transformation generator allows one to take into account the effect of hole interactions with the short-range spin waves and to describe the single-hole ground state. Obtained results are very close to ones of the self-consistent Born approximation. Further accounting of the long-range spin-wave interaction is possible on a perturbative basis. Spin-wave exchange and an effective interaction due to minimization of the number of broken antiferromagnetic bonds are included in the effective quasiparticle Hamiltonian. The two-hole bound state problem is solved using a Bethe-Salpeter equation. The only bound state found to exist in the region of 1 <(t/J)<5 is the d wave. Both types of the hole-hole interaction are important for its formation. A discussion of the possible relation of the obtained results to the problem of superconductivity in real systems is presented.

【 授权许可】

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