  A major outstanding problem in solar physics is the confinement of the solar
tachocline, the thin shear layer that separates nearly solid-body rotation in
the radiative interior from strong differential rotation in the convection
zone. Here, we present the first 3-D, global solar simulation in which a
tachocline is confined by a self-excited dynamo. The non-axisymmetric magnetism
is initially built in the convection zone and then diffusively imprints
downward. Additionally, the field is locally amplified throughout the radiative
interior by vigorous horizontal motions that arise from equatorial Rossby waves
and possibly shear instabilities. Our work thus challenges the long-held notion
that the Sun's dynamo magnetic field is amplified only as deep as the
tachocline and stored in a quiescent radiative interior.
