We examine the excitations of a quasi-one dimensional easy plane antiferromagnet, in a symmetry breaking applied magnetic field. The antiferromagnetic exchange includes a small Dzyaloshinski Moriya component that produces the easy plane. In the classical continuum limit, this system is described by a double-sine-Gordon field theory, which supports soliton excitations and the multi spin wave bou...

The spectral properties of the 1-D Hubbard model are obtained from quantum Monte Carlo simulations using the maximum entropy method. The one-particle excitations are characterized by dispersive cosine-like bands. Velocities for spin-and charge excitations are obtained that lead to a conformal charge c = 0:98 0:05 for the largest system simulated (N = 84). An exact sum-rule for the spin-excitati...

We describe manipulation of the radio sensitivity of the nucleotide base driven by the spin blockade mechanism of diffusive free radicals against ionizing radiation. We theoretically propose a mechanism which uses the simultaneous application of circularly polarized light and an external magnetic field to control the polarization of the free radicals and create S=1 electron-hole spin excitation...

Combining recent and new inelastic neutron scattering data for the molecular cyclic cluster Cr8 produces a deep understanding of the low lying excitations in bipartite antiferromagnetic Heisenberg rings. The existence of the L band, the lowest rotational band, and the E band, essentially spin wave excitations, is confirmed spectroscopically. The different significance of these excitations and t...

Transport experiments are sensitive to charged ‘quasiparticle’ excitations of the fractional quantum Hall effect. Inelastic Raman scattering experiments have probed an amazing variety of other excitations: excitons, rotons, bi-rotons, trions, flavor altering excitons, spin waves, spin-flip excitons, and spin-flip rotons. This paper reviews the status of our theoretical understanding of these ex...

The particle hole and delta hole excitations are well known elementary excitation modes for pion propagator in nuclear matter. But, the excitation also involves antiparticles, namely, nucleon-antinucleon, antidelta-nucleon and delta-antinucleon excitations. These are important for high energy-momentum as well, and not studied before. In this paper, we give both the formulae and the numerical ca...

The formalism for computing the gravitational power radiation from excitations on cosmic strings forming a junction is presented and applied to the simple case of co-planar strings at a junction when the excitations are generated along one string leg. The effects of polarization of the excitations and of the back-reaction of the gravitational radiation on the small scale structure of the string...

We study the problem of spin diffusion in magnetic systems without longrange order. We discuss the example of the 1D spin chain. For the system described by the Heisenberg Hamiltonian we show that there are no diffusive excitations. However, the addition of an arbitrarily small dissipation term, such as the spin-phonon interaction leads to diffusive excitations in the long time limit. For those...

Large-basis shell model studies of low-lying excitations in light nuclei from He to Li have been performed with a multivalued G-matrix effective interaction, as recently suggested by Haxton et al.. Calculations were performed relative to the vacuum (“no core”) using very large, separable model spaces containing all excitations with unperturbed energies up to 8h̄Ω. Using G matrices derived from a...

We use neutron scattering to study spin excitations in single crystals of LiFe_{0.88}Co_{0.12}As, which is located near the boundary of the superconducting phase of LiFe_{1-x}Co_{x}As and exhibits non-Fermi-liquid behavior indicative of a quantum critical point. By comparing spin excitations of LiFe_{0.88}Co_{0.12}As with a combined density functional theory and dynamical mean field theory calc...