Chirality of superfluid 3He-A

P. M. Walmsley; A. I. Golov

doi:10.1103/physrevlett.109.215301

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arXiv · 1209.1627

Chirality of superfluid 3He-A

P. M. Walmsley·A. I. Golov

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Abstract

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.

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P. M. Walmsley, A. I. Golov. 2012-09-07. Chirality of superfluid 3He-A. https://doi.org/10.1103/physrevlett.109.215301

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