Charge and spin structures of a d{sub x{sup 2}{minus}y{sup 2}} superconductor in the proximity of an antiferromagnetic Mott insulator
- Department of Physics, University of California, Santa Barbara, California 93106-9530 (United States)
- Institute for Solid State Physics, University of Tokyo, 7-22-1 Roppongi, Minato-ku, Tokyo 106 (Japan)
To the Hubbard model on a square lattice we add an interaction W that depends upon the square of a near-neighbor hopping. We use zero-temperature quantum Monte Carlo simulations on lattice sizes up to 16{times}16, to show that at half-filling and constant value of the Hubbard repulsion, the interaction W triggers a quantum transition between an antiferromagnetic Mott insulator and a d{sub x{sup 2}{minus}y{sup 2}} superconductor. With a combination of finite-temperature quantum Monte Carlo simulations and the maximum entropy method, we study spin and charge degrees of freedom in the superconducting state. We give numerical evidence for the occurrence of a finite-temperature Kosterlitz-Thouless transition to the d{sub x{sup 2}{minus}y{sup 2}} superconducting state. Above and below the Kosterlitz-Thouless transition temperature, T{sub KT}, we compute the one-electron density of states N({omega}), the spin relaxation rate 1/T{sub 1}, as well as the imaginary and real part of the spin susceptibility {chi}({rvec q},{omega}). The spin dynamics are characterized by the vanishing of 1/T{sub 1} and divergence of Re{chi}{bold (}{rvec q}=({pi},{pi}),{omega}=0{bold )} in the low-temperature limit. As T{sub KT} is approached N({omega}) develops a pseudogap feature and below T{sub KT}Im{chi}{bold (}{rvec q}=({pi},{pi}),{omega}{bold )} shows a peak at finite frequency. {copyright} {ital 1997} {ital The American Physical Society}
- OSTI ID:
- 554362
- Journal Information:
- Physical Review, B: Condensed Matter, Vol. 56, Issue 23; Other Information: PBD: Dec 1997
- Country of Publication:
- United States
- Language:
- English
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