The spin dynamics of a doped two-leg spin ladder is investigated by numerical techniques. We show that a hole pair-magnon boundstate evolves at finite hole doping into a sharp magnetic excitation below the two-particle continuum. This is supported by a field theory argument based on a $\mathrm{SO}(6)$ -symmetric ladder. Similarities and differences with the resonant mode of the high- ${T}_{C}$ cuprates are discussed.The spin dynamics of a doped two-leg spin ladder is investigated by numerical techniques. We show that a hole pair-magnon boundstate evolves at finite hole doping into a sharp magnetic excitation below the two-particle continuum. This is supported by a field theory argument based on a $\mathrm{SO}(6)$-symmetric ladder. Similarities and differences with the resonant mode of the high-${T}_{C}$ cuprates are discussed.

arXiv:cond-mat/0402011Physical Review BJun 18, 200421 citations

Quantum Monte Carlo study of superconductivity in the two-leg ladder and low dimensional correlated systems

Takashi Yanagisawa, Yamaji K.

Physica C SuperconductivityMay 12, 20060 citations

Absence of Luther-Emery superconducting phase in the three-band model for cuprate ladders

Jeong-Pil Song, S. Mazumdar, Rudolf Torsten Clay

Correlated-electron theories of superconductivity in layered cuprates often start from the premise of a gapped spin-liquid phase proximate to the superconducting state. This assumption is justified based on analytical and numerical demonstrations of a superconducting Luther-Emery phase in the doped 2-leg one-band Hubbard ladder, and the perceived analogy between coupled ladders and the two-dimensional ${\mathrm{CuO}}_{2}$ layer. We demonstrate from accurate density matrix renormalization group studies the absence of the superconducting Luther-Emery phase in the doped 2-leg three-band ladder consisting of both copper and oxygen, even as the spin gap is large in the undoped three-band ladder. For realistic oxygen-oxygen hopping and Hubbard repulsion on the oxygen atoms, density-density rather than pairing correlations are dominant at long range. This result is equally valid whether or not the oxygens outside the ladder proper, over and above the rung and leg oxygens, are included in the computation. These results demonstrate the critical importance of oxygen orbitals, and raise disturbing questions about the applicability of many of the existing correlated-electron theories of superconductivity.Correlated-electron theories of superconductivity in layered cuprates often start from the premise of a gapped spin-liquid phase proximate to the superconducting state. This assumption is justified based on analytical and numerical demonstrations of a superconducting Luther-Emery phase in the doped 2-leg one-band Hubbard ladder, and the perceived analogy between coupled ladders and the two-dimensional ${\mathrm{CuO}}_{2}$ layer. We demonstrate from accurate density matrix renormalization group studies the absence of the superconducting Luther-Emery phase in the doped 2-leg three-band ladder consisting of both copper and oxygen, even as the spin gap is large in the undoped three-band ladder. For realistic oxygen-oxygen hopping and Hubbard repulsion on the oxygen atoms, density-density rather than pairing correlations are dominant at long range. This result is equally valid whether or not the oxygens outside the ladder proper, over and above the rung and leg oxygens, are included in the computation. These results demonstrate the critical importance of oxygen orbitals, and raise disturbing questions about the applicability of many of the existing correlated-electron theories of superconductivity.

arXiv:2010.10609Physical review. B./Physical review. BSep 13, 20219 citations

Superconductivity of the spin ladder system: pairing and spin gap

Naoki Fujiwara

APSMar 1, 20040 citations

\mathrm{SO}(6)

-symmetric ladder. Similarities and differences with the resonant mode of the high-

{T}_{C}

cuprates are discussed.

{\mathrm{CuO}}_{2}

layer. We demonstrate from accurate density matrix renormalization group studies the absence of the superconducting Luther-Emery phase in the doped 2-leg three-band ladder consisting of both copper and oxygen, even as the spin gap is large in the undoped three-band ladder. For realistic oxygen-oxygen hopping and Hubbard repulsion on the oxygen atoms, density-density rather than pairing correlations are dominant at long range. This result is equally valid whether or not the oxygens outside the ladder proper, over and above the rung and leg oxygens, are included in the computation. These results demonstrate the critical importance of oxygen orbitals, and raise disturbing questions about the applicability of many of the existing correlated-electron theories of superconductivity.