  Confinement and surface roughness (SR) effects on the magnitude of the
persistent current are analized for ballistic bidimensional metallic samples.
Depending on the particular geometry, localized border states can show up at
half filling. These border states contribute coherently to the persistent
current and its magnitude is enhanced with respect to their value in the absent
of confinement. A linear scaling of the typical current $I_{typ}$ with the
number of conduction channels M is obtained. This result is robust with respect
to changes in the relevant lengths of the samples and to the SR. Possible links
of our results to experiments are also discussed.

Mesoscale and Nanoscale Physics