  A natural mechanism for finite temperature quark confinement arises via the
coupling of the adjoint Polyakov loop to the chromomagnetic field. Lattice
simulations and analytical results both support this hypothesis. Finite
temperature SU(3) lattice simulations show that a large external coupling to
the chromomagnetic field restores confinement at temperatures above the normal
deconfining temperature. A one-loop calculation of the effective potential for
SU(2) gluons in a background field shows that a constant chromomagnetic field
can drive the Polyakov loop to confining behavior, and the Polyakov loop can in
turn remove the well-known tachyonic mode associated with gluons in an external
chromomagnetic field. For abelian background fields, tachyonic modes are
necessary for confinement at one loop.
