Related papers: Transverse spin waves in isotropic ferromagnets
Recent experiments in a mixture of two hyperfine states of trapped Bose gases show behavior analogous to a spin-1/2 system, including transverse spin waves and other familiar Leggett-Rice-type effects. We have derived the kinetic equations…
The asymmetry of the modal profiles for dipole-exchange spin waves propagating in in-plane magnetized ferromagnetic films at a right angle to the applied magnetic field has been investigated theoretically. It was found that in the…
The pseudogap metal phase of the hole-doped cuprates can be described by small Fermi surfaces of electron-like quasiparticles, which enclose a volume violating the Luttinger relation. This violation requires the existence of additional…
Ferromagnetism in the t-t' Hubbard model is investigated on a square lattice. Correlation effects in the form of self-energy and vertex corrections are systematically incorporated within a spin-rotationally-symmetric scheme which explicitly…
We consider two-dimensional Fermi liquids in the vicinity of a quantum transition to a phase with commensurate, antiferromagnetic long-range order. Depending upon the Fermi surface topology, mean-field spin-density-wave theory predicts two…
Using density functional theory in a time dependent approach we determine the frequencies of the compressional modes of the normal phase of a Fermi gas at unitarity as a function of its polarization. Our energy functional accounts for the…
In this paper we study a class of exactly solvable Kondo-Heisenberg toy models in one dimension, with the goal of comparing the exact low-energy excitations of the ferromagnetic ground state to the approximate solution obtained from spin…
Applying the local density and dynamical mean field approximations to paramagnetic \gamma-iron we revisit the problem of theoretical description of magnetic properties in a wide temperature range. We show that contrary to \alpha-iron, the…
The spin liquid state of the antiferromagnetic Heisenberg model on a triangular lattice is studied within the self-consistent Green's function method. It is shown that the spin excitation spectra is gapless, and ground-state energy per site…
We investigate the propagation of spin excitations in a one-dimensional (1D) ferromagnetic Bose gas. While the spectrum of longitudinal spin waves in this system is sound-like, the dispersion of transverse spin excitations is quadratic…
Spontaneous magnon decays in an $S=\frac{1}{2}$ Heisenberg antiferromagnet on the equilateral triangular prism are investigated in terms of modified magnon Green's functions. In one dimension, the so-called infrared divergence prevents us…
In the new van der Waals Kondo-lattice Fe$_3$GeTe$_2$, itinerant ferromagnetism and heavy fermionic behaviour coexist. Both the key properties of such a system namely a spin-polarized Fermi surface and a low Fermi momentum are expected to…
It has been known that the spin-wave dispersion, which is usually symmetric in the momentum space with respect to ${\bf q}=0$, can be asymmetric in the presence of the Dzyaloshinskii-Moriya (DM) interaction and an applied magnetic field.…
We theoretically study a finite size $SF_1NF_2$ spin valve, where a normal metal ($N$) insert separates a thin standard ferromagnet ($F_1$) and a thick half-metallic ferromagnet ($F_2$). For sufficiently thin superconductor ($S$) widths…
We analyze the properties of a single impurity immersed in a Fermi sea. At positive energy and scattering lengths, we show that the system possesses a well-defined but metastable excitation, the repulsive polaron, and we calculate its…
In the setting of general initial data and whole space we perform a rigorous analysis of the quasineutral limit for a hydrodynamical model of a viscous plasma with capillarity tensor represented by the Navier Stokes Korteweg Poisson system.…
We introduce a novel approach for the investigation of spin-wave excitations in itinerant ferromagnets. Our theory is based on a variational treatment of general multi-band Hubbard models which describe elements and compounds of transition…
Magnons, the spin-wave quanta, are disturbances that embody a wave propagating through a background medium formed by ordered magnetic moments. In an isotropic Heisenberg system, these disturbances vary in a continuous manner around an…
We investigate the effect of Coulomb drag resistance in a bilayer system of strongly correlated electron liquids magnetized by an in-plane field employing the framework of hydrodynamic theory. We identify a mechanism for drag…
The quasistatic approach is used to analyze the criterion of ferromagnetism for two-dimensional (2D) systems with the Fermi level near Van Hove (VH) singularities of the electron spectrum. It is shown that the spectrum of spin excitations…