Long wavelength spin dynamics of ferromagnetic condensates

@misc{citeulike:1750586, abstract = {We obtain the equations of motion for a ferromagnetic Bose condensate of arbitrary spin in the long wavelength limit. We find that the magnetization of the condensate is described by a non-trivial modification of the Landau-Lifshitz equation, in which the magnetization is advected by the superfluid velocity. This hydrodynamic description, valid when the condensate wavefunction varies on scales much longer than either the density or spin healing lengths, is both physically more transparent and computationally simpler than the corresponding time-dependent Gross-Pitaevskii equation. We discuss the conservation laws of the theory and its application to the analysis of the stability of magnetic helices and Larmor precession. Precessional instabilities in particular provide a novel physical signature of dipolar forces.}, author = {Lamacraft, Austen }, citeulike-article-id = {1750586}, eprint = {0710.1848}, keywords = {excitations, hydrodynamics, spinor}, month = {Oct}, posted-at = {2007-10-11 08:05:28}, priority = {5}, title = {Long wavelength spin dynamics of ferromagnetic condensates}, url = {http://arxiv.org/abs/0710.1848}, year = {2007} }

TY - ELEC ID - citeulike:1750586 L3 - citeulike-article-id:1750586 TI - Long wavelength spin dynamics of ferromagnetic condensates N2 - We obtain the equations of motion for a ferromagnetic Bose condensate of arbitrary spin in the long wavelength limit. We find that the magnetization of the condensate is described by a non-trivial modification of the Landau-Lifshitz equation, in which the magnetization is advected by the superfluid velocity. This hydrodynamic description, valid when the condensate wavefunction varies on scales much longer than either the density or spin healing lengths, is both physically more transparent and computationally simpler than the corresponding time-dependent Gross-Pitaevskii equation. We discuss the conservation laws of the theory and its application to the analysis of the stability of magnetic helices and Larmor precession. Precessional instabilities in particular provide a novel physical signature of dipolar forces. KW - excitations KW - hydrodynamics KW - spinor AU - Lamacraft, Austen PY - 2007/Oct/09/ UR - http://arxiv.org/abs/0710.1848 ER -