  We analyze the relation between Faddeev-Popov eigenmodes and gluon-momentum
components in the Coulomb gauge using SU(3) lattice QCD. In the Coulomb gauge,
the color-Coulomb energy is largely enhanced by near-zero Faddeev-Popov
eigenmodes, which would lead to the confining potential. By the
ultraviolet-momentum gluon cut, the color-Coulomb energy and the Faddeev-Popov
spectrum are almost unchanged. In contrast to the ultraviolet insensitivity,
the color-Coulomb energy and the Faddeev-Popov eigenmodes drastically change by
infrared-momentum gluon cut. Without infrared gluons, the color-Coulomb energy
tends to become non-confining, and near-zero Faddeev-Popov eigenmodes vanish.
We also investigate the full FP eigenmodes, and find that infrared gluons
widely influence both high and low Faddeev-Popov eigenmodes.
