Quantum vortex dipole as a probe of the normal component distribution

The paper explores the dynamics of quantum vortex dipoles in a strongly interacting, spin-imbalanced Fermi superfluid at zero temperature. Using time-dependent density functional theory, it demonstrates how spin polarization shapes dipole motion, leading to deflection, energy loss, or rapid annihilation. The results reveal a hidden normal component even at zero temperature and show that vortex dipoles can serve as sensitive probes of exotic superfluid phases such as the Fulde–Ferrell–Larkin–Ovchinnikov state.