  The low-temperature shrinking of the vortex core (Kramer-Pesch effect) is
studied for an isolated single vortex for chiral p-wave and s-wave
superconducting phases. The effect of nonmagnetic impurities on the vortex core
radius is numerically investigated in the Born limit by means of a
quasiclassical approach. It is shown that in the chiral p-wave phase the
Kramer-Pesch effect displays a certain robustness against impurities owing to a
specific quantum effect, while the s-wave phase reacts more sensitively to
impurity scattering. This suggests chiral p-wave superconductors as promising
candidates for the experimental observation of the Kramer-Pesch effect.
