Orbital dynamics of3He-A in the presence of a heat flow and a magnetic field

Abstract

The equation of motion of the orbital axis l of ³He-A has been solved numerically for a situation in which the liquid is contained in the channel between two parallel planes when there is a flow of heat between the planes and a magnetic field applied perpendicular to them. For zero field, the texture with l uniform and perpendicular to the planes is stable, and there are time-dependent solutions satisfying the same boundary conditions. Precessing solitary wave solutions are found when l is constrained to have a direction on one plane opposite to that on the other. A magnetic field destabilises the texture of uniform l and with increasing field a time-independent state in which l spirals, a state with time-dependent l and a state with l perpendicular to the field over most of the channel are found successively. Three-dimensional geometries and persistent current decay through orbital motion is discussed.