  The influence of various matter fields on the confining and
finite-temperature properties of the (2+1)d Georgi-Glashow model is explored.
At zero temperature, these fields are W-bosons, which play the role of heavy
nodes, through which the quark-antiquark string passes. This fact is shown to
increase by a factor $4\sqrt{2}$ the absolute value of the coefficient at the
1/R-term in the large-distance potential with respect to that of the Nambu-Goto
string in 3d. The string tension also acquires a positive correction, which is,
however, exponentially small. At finite temperature, the matter fields of
interest are massless fundamental quarks, which diminish the deconfinement
critical temperature by way of an additional attraction of a monopole and an
antimonopole inside their molecules through the quark zero modes. It is
demonstrated that, outside the BPS-limit, when the number of massless flavors
is 4 or larger, the deconfinement phase transition occurs already at the
temperatures of the order of the temperature of dimensional reduction. In the
BPS limit, this critical number of flavors is 3. Since the temperature of
dimensional reduction is exponenetially small and since monopoles are
instantons in (2+1)d, these numbers can be compared with the one in the
instanton-liquid model of 4d QCD, at which the chiral phase transition occurs
at a vanishingly small temperature. The latter number is known to be of the
order of 5, so that the results of the two models are quite close to each
other.
