Monday, September 10, 2012

1209.1627 (P. M. Walmsley et al.)

Chirality of superfluid 3He-A    [PDF]

P. M. Walmsley, A. I. Golov
We have used torsional oscillators, containing disk-shaped slabs of superfluid 3He-A, to probe the chiral orbital textures created by cooling into the superfluid state while continuously rotating. Comparing the observed flow-driven textural transitions with numerical simulations of possible textures shows that an oriented monodomain texture with l antiparallel to the angular velocity Omega_0 is left behind after stopping rotation. The bias towards a particular chirality, while in the vortex state, is due to the inequivalence of energies of vortices of opposite circulation. When spun-up from rest, the critical velocity for vortex nucleation depends on the sense of rotation, Omega, relative to that of l. A different type of vorticity, apparently linked to the slab's rim by a domain wall, appears when Omega is parallel to l.
View original:

No comments:

Post a Comment