  We investigate cooling mechanisms in magneto-optically and magnetically
trapped erbium. We find efficient sub-Doppler cooling in our trap, which can
persist even in large magnetic fields due to the near degeneracy of two Lande g
factors. Furthermore, a continuously loaded magnetic trap is demonstrated where
we observe temperatures below 25 microkelvin. These favorable cooling and
trapping properties suggest a number of scientific possibilities for rare-earth
atomic physics, including narrow linewidth laser cooling and spectroscopy,
unique collision studies, and degenerate bosonic and fermionic gases with
long-range magnetic dipole coupling.
