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Using NMR techniques we monitor the structure and number of vortices in a cylindrical container, rotating at constant angular velocity Ω, before and after the passage of the A-B interface. The initial A phase contains the equilibrium number of vortices. The final B phase is found to have a deficit of vortices which depends nonmonotonically on the measured time t AB of the A→B transition. We argue that a vortex layer is formed in front of the moving A-B interface. The measured vortex deficit can be understood by analyzing the stability of the layer

We have observed spin-mass vortices (SMV) in superfluid $^{3}\mathit{B}$. The SMV is a combined topological object made up of a vortex line with mass current and a disclination line with spin current. It is also a termination line of a planar defect, the so-called \ensuremath{\theta} soliton. The SMVs are bound either as pairs or to the container wall by the soliton. They are nucleated when a rotating $^{3}\mathrm{He}$ sample cools slowly through the A\ensuremath{\rightarrow}B phase transition. The identification of the SMV is based on the NMR signatures of the soliton.

We present experimental proof that in rotating {sup 3}He-{ital B} the vortex-core transition temperature {ital T}{sub {ital V}} separates axisymmetric vortices above {ital T}{sub {ital V}} from vortices with spontaneously broken axial symmetry below {ital T}{sub {ital V}}. The nonaxisymmetry is observed in the presence of coherent spin precession as a new soft Goldstone mode, manifested as oscillations and spiral twisting of the core anisotropy axis. These are driven by the precessing spin via spin-orbit coupling and lead to magnetic relaxation from viscous losses, which depend on vortex pinning.

The order-parameter texture has been studied in rotating {sup 3}He-{ital B} in the vortex-free state with NMR techniques. A sequence of textural phase transitions is observed with increasing rotation speed. It is generated by competing interactions with magnetic field, surfaces, and rotation. Two surface interactions are extracted: the susceptibility anisotropy at the wall and the gyromagnetism due to a magnetic-field-induced surface supercurrent. The results are consistent with an order-parameter structure approaching the planar state with diffuse quasiparticle scattering at the wall.

Experiments with negative ions in rotating superfluid 3He-A show strong retardation and deformation of ion pulses drifting parallel to the angular velocity Ω. This is caused by the interaction between the ions and the l texture in the soft cores of A-phase vortices. The interaction is mediated by the anisotropic ion mobility: v=μ⊥E-Δμ(E·l)l. The (Ω,T) dependence of the retardation is explained by a model that assumes focusing of ions into the vortex cores, along which the mobility μc is lower than that in the bulk liquid, μ⊥. We find μc=μ⊥-0.6Δμ.

First experiments suggesting the presence of singular vortices in rotating /sup 3/He-A are reported. Our studies on the interaction between negative ions and vortex textures verify the existence of the continuous vortices seen earlier by NMR, but evidence for a new vortex state with high ion mobility along the core is also found. The nucleation of the new vortex depends on the external magnetic field and the rotation history of the sample.