Anisotropy of incommensurate spin and charge fluctuations in detwinned YBa${}_2$Cu${}_3$O${}_{6+\delta }$

Abstract

Motivated by a recent neutron scattering experiment on detwinned YBa${}_2$Cu${}_3$O${}_{6+\delta }$ superconductor, we examine the frequency and doping dependence of the anisotropy in the spin and charge fluctuation arising from the coupling between the plane and the chain. Starting from the two-dimensional $t$-$t^{{}^{\prime }}$-$J$ model and using the random-phase approximation (RPA), we find a pronounced anisotropy of the incommensurate (IC) peaks in the spin channel, namely the peak intensity at the $(\pi \pm \delta ,\pi )$ direction is stronger than that at the $(\pi ,\pi \pm \delta )$ direction in a wide frequency range from $\omega =0.2J$ to the resonance frequency ${\omega }_r=0.35J$. Above the resonance frequency, the IC peaks reemerge. Their intensities shift to the diagonal direction and no anisotropy exists along the two diagonal directions. We find that this anisotropy is robust with respect to the possible variation of the RPA correction factor and to the dopings. The charge fluctuation is also found to be incommensurate for all energies considered and peak at $(0,\delta )$ and $(\delta ,0)$. An anisotropy in its IC peak intensity along the $k_x$ and the $k_y$ direction exists, but in sharp contrast to the spin channel, the maximum intensity of the IC peak is along the $k_y$ direction. Moreover, the IC peak in the charge channel exhibits an upward dispersion, in contrast to the downward dispersion below the spin resonance frequency for the spin IC peak. We explain these features based on the effect of the plane-chain coupling on the topology of the Fermi surface.

8 pages

References in corpus (14)

• Quantum Magnetic Excitations from Stripes in Copper-Oxide Superconductors
• Two-Dimensional Geometry of Spin Excitations in the High Temperature Superconductor YBa2Cu3O6+x
• One-dimensional nature of the magnetic fluctuations in YBa${}_2$Cu${}_3$O${}_{6.6}$
• Slave Boson Approach to The Neutron Scattering in YBCO Superconductors
• The Relation of Neutron Incommensurability to Electronic Structure in High Temperature Superconductors
• Frequency Evolution of Neutron Peaks Below Tc: Commensurate and Incommensurate Structure in LaSrCuO and YBaCuO
• Superfluid anisotropy in YBCO: Evidence for pair tunneling superconductivity
• Effect of Proximity Coupling of Chains and Planes on the Penetration Depth Anisotropy in Y_1Ba_2Cu_3O_7
• A Consistent Picture for Resonance Neutron Peak and ARPES Spectra in High-Tc Superconductors
• Anisotropic spin and charge excitations in superconductors: signature of electronic nematic order
• Doping dependence of the resonance peak and incommensuration in high-$T_c$ superconductors
• Fermi-liquid based theory for the in-plane magnetic anisotropy in untwinned high-T${}_c$ superconductors
• Magnetic Coherence in Cuprate Superconductors
• Effects of Charge Density Modulation on Incommensurate Antiferromagnetism: Ginzburg-Landau Study

Cited by in corpus (4)

• Magnetic excitations and their anisotropy in YBCO: slave-boson mean-field analysis of bilayer t-J model
• Spin excitations in nickelate superconductors
• Theory for Inelastic Neutron Scattering in Orthorhombic High-Tc Superconductors
• Difficulty in the Fermi-Liquid-Based Theory for the In-Plane Magnetic Anisotropy in Untwinned High-T_c Superconductor