Textures and NMR spectra of a superfluid 3He-A phase confined in rotating narrow cylinders

Abstract

We confine a superfluid 3He-A phase in narrow cylinders, these radii are 0.05 and 0.1 mm. The system is rotated around the cylinder axis, and its rotation velocity ranges between −6.28 and 6.28 rad/s. The strong magnetic field (22 mT) is applied along cylinder axis. In these systems, we determined l - and d -textures by minimizing GL-free energies. In the case of the small cylinder ( R=0.05 mm) a dipole locked and a dipole unlocked Mermin–Ho textures are obtained as local minimum free energy states. In the case of the large cylinder ( R=0.1 mm), a single vortex and a three vortices states are obtained. The stability of each state depends on the rotating velocity. A vortex charge change of two quanta occurs by a pair of continuous vortices coming in and going out. For each case, the NMR spectrum of the transverse resonance mode is calculated by using a finite element method (FEM). Using the FEM the boundary condition of spin wave mode is strictly imposed and the higher resonance mode is also calculated. The calculated result agrees well with empirical data.