Excitation spectrum of the homogeneous spin liquid

0 The Spin Excitation Spectrum in Superconducting

P. Bourges, Y. Sidis, H.F. Fong, L.P. Regnault, J. Bossy, A. Ivanov, B. Keimer 1 Laboratoire Léon Brillouin, CEA-CNRS, CE Saclay, 91191 Gif sur Yvette, France 2 Department of Physics, Princeton University, Princeton, NJ 08544, USA 3 CEA Grenoble, Département de Recherche Fondamentale sur la matière Condensée, 38054 Grenoble cedex 9, France 4 CNRS-CRTBT, BP 166, 38042 Grenoble cedex 9, France 5 ...

On the Infimum of the Excitation Spectrum of a Homogeneous Bose Gas

We consider a second quantized homogeneous Bose gas in a large cubic box with periodic boundary conditions, at zero temperature, and in the grand canonical setting (the chemical potential μ is fixed, the number of particles can vary). The interaction potential has a positive Fourier transform. We define the infimum of the excitation spectrum as the infimum of the grandcanonical Hamiltonian rest...

Low Energy Singlets in the Excitation Spectrum of the Spin Tetrahedra System Cu2Te2O5Br2

Low energy Raman scattering of the s=1/2 spin tetrahedra system Cu2Te2O5Br2 is dominated by an excitation at 18 cm corresponding to an energy ES = 0.6∆, with ∆ the spin gap of the compound. For elevated temperatures this mode shows a soft mode-like decrease in energy pointing to an instability of the system. The isostructural reference system Cu2Te2O5Cl2 with a presumably larger inter-tetrahedr...

Temperature variation of the elementary excitation spectrum of thin liquid-4He films.

Superstripes and the excitation spectrum of a spin-orbit-coupled Bose-Einstein condensate.

Using Bogoliubov theory we calculate the excitation spectrum of a spinor Bose-Einstein condensed gas with an equal Rashba and Dresselhaus spin-orbit coupling in the stripe phase. The emergence of a double gapless band structure is pointed out as a key signature of Bose-Einstein condensation and of the spontaneous breaking of translational invariance symmetry. In the long wavelength limit the lo...