相关论文: Incommensurate Charge and Spin Fluctuations in d-w…
Accurate determination of the full momentum-dependent spin susceptibility $\chi(\mathbf{q}) $ is very important for the description of magnetism and superconductivity. While in principle the formalism for calculating $\chi(\mathbf{q})$ in…
Collective excitations both for spin- and charge-channels are investigated in incommensurate spin density wave (or stripe) states on two-dimensional Hubbard model. By random phase approximation, the dynamical susceptibility \chi(q,\omega)…
We study spin and charge susceptibilities in the d-wave superconducting state whose underlying electronic dispersion is anisotropic due to the formation of the electronic nematic order. We show that the amplitude of the incommensurate peaks…
We explain the effects of superconductivity on the incommensurate magnetic response $\chi''(q,\omega)$ observed in inelastic neutron scattering measurements on La$_{2-x}$Sr$_x$CuO$_4$. We show that a spin-fermion model correctly describes…
We study the single-particle spectral properties of electrons coupled to quasicritical charge and spin fluctuations close to a stripe-phase, which is governed by a Quantum Critical Point near optimum doping. We find that spectral weight is…
We present analytic results for the polarizabilities, $\chi({\bf Q},\omega)$, in the charge, spin, and current channels for two-dimensional s- and d-wave superconductors for large momentum transfer. A collective mode in the charge channel…
It is shown that in the t-J model of Cu-O planes at low frequencies the dynamic spin structure factor is peaked at incommensurate wave vectors (1/2+-delta,1/2)$, (1/2,1/2+-delta). The incommensurability is connected with the momentum…
We calculate the wave-vector dependent electronic spin susceptibility $\chi_{\alpha\beta}(\mathbf q, \mathbf H_0)$ of a d-wave superconductor in uniform magnetic field $\mathbf{H}_0$ with Pauli pair-breaking. We find that the transverse…
We explore the ferromagnetic quantum critical point in a three-dimensional semimetallic system with upward- and downward-dispersing bands touching at the Fermi level. Evaluating the static spin susceptibility to leading order in the…
In $\rm Sr_2RuO_4$ the spin excitation spectrum is dominated by incommensurate fluctuations at q=(0.3 0.3 q$_z$), which arise from Fermi-surface nesting. We show that upon Ti substitution, known to suppress superconductivity, a short range…
General theory of d-wave quasiparticles coupled to phase fluctuations of superconducting order parameter is discussed. In the charge sector the superfluid density is found to conform to Uemura scaling, and the charge renormalization factor…
Based on recent magnetic-quantum-oscillation, ARPES, neutron-scattering and other data, we propose that superconductivity in the cuprates occurs via a convenient matching of the spatial distribution of incommensurate spin fluctuations to…
The dynamic spin susceptibility, $\chi''(\omega)$, has been measured over the energy range of $2 \leq \omega \leq 10$ meV for overdoped La$_{2-x}$Sr$_{x}$CuO$_{4}$. Incommensurate (IC) spin excitations are observed at 8 K for all…
Neutron diffraction studies of Ba(Fe[1-x]Co[x])2As2 reveal that commensurate antiferromagnetic order gives way to incommensurate magnetic order for Co compositions between 0.056 < x < 0.06. The incommensurability has the form of a small…
We present a coherent scenario for the physics of cuprate superconductors, which is based on a charge-driven inhomogeneity, i.e. the ``stripe phase''. We show that spin and charge critical fluctuations near the stripe instability of…
We consider incommensurate $d$-density wave order in underdoped high temperature superconductors. We find that Fermi surface reconstruction can correctly capture the phenomenology of the recent quantum oscillation experiments that suggest…
We revisit the dynamic spin susceptibility, $\chi(q,\omega)$, of one-dimensional interacting fermions. To second order in the interaction, backscattering results in a logarithmic correction to $\chi(q,\omega)$ at $q\ll k_F$, even if the…
The leading superconducting instabilities of the two-dimensional extended repulsive one-band Hubbard model within spin-fluctuation pairing theory depend sensitively on electron density, band and interaction parameters. We map out the phase…
For the superconducting phase with a d-wave order parameter and zero temperature the magnetic susceptibility of the t-J model is calculated using the Mori projection operator technique. Conditions for the appearance of an incommensurate…
We investigate the imaginary part of the wave vector dependent dynamic spin susceptibility in Sr$_2$(Ru$_{0.99}$Ti$_{0.01}$)O$_4$ as a function of temperature using neutron scattering. At T=5 K, two-dimensional incommensurate (IC) magnetic…