  Quantized vortex core structure is theoretically investigated in Fermion
superfluids with population imbalance for two atom species of neutral atom
clouds near a Feshbach resonance. In contrast with vortex core in balance case
where the quantum depletion makes a vortex visible through the density profile
measurement, the vortex core is filled in and becomes less visible because the
quantized discrete bound states are occupied exclusively by the majority
species. Yet it is shown that the core can be visible through the minority
density profile experiment using phase contrast imaging, revealing an
interesting opportunity to examine low-lying Fermionic core bound states
unexplored so far.
