  The magnetization in a magnetic microdot made from soft magnetic materials
can have a vortex-like ground state structure resulting from competition
between the exchange and dipolar interactions. Normal mode magnon frequencies
for such dots are calculated taking into account both exchange and
magnetostatic effects. The presence of a low-lying mode as well as doublet
structure with small splitting is demonstrated. Estimates of the mode
frequencies for permalloy dots are obtained, and the possibility of
experimental detection of such modes is discussed.

Materials Science