  The infrared behavior of the gluon propagator is directly related to
confinement in QCD. Indeed, the Gribov-Zwanziger scenario of confinement
predicts an infrared vanishing (transverse) gluon propagator in Landau-like
gauges, implying violation of reflection positivity and gluon confinement.
Finite-volume effects make it very difficult to observe (in the minimal Landau
gauge) an infrared suppressed gluon propagator in lattice simulations of the
four-dimensional case. Here we report results for the SU(2) gluon propagator in
a gauge that interpolates between the minimal Landau gauge (for gauge parameter
lambda equal to 1) and the minimal Coulomb gauge (corresponding to lambda = 0).
For small values of lambda we find that the spatially-transverse gluon
propagator D^tr(0,|\vec p|), considered as a function of the spatial momenta
|\vec p|, is clearly infrared suppressed. This result is in agreement with the
Gribov-Zwanziger scenario and with previous numerical results in the minimal
Coulomb gauge. We also discuss the nature of the limit lambda -> 0 (complete
Coulomb gauge) and its relation to the standard Coulomb gauge (lambda = 0). Our
findings are corroborated by similar results in the three-dimensional case,
where the infrared suppression is observed for all considered values of lambda.
