  We show that a high-scale leptogenesis can be consistent with a low-scale
one-loop neutrino mass generation. Our models are based on the SU(3)_c\times
SU(2)_L\times U(1)_Y\times U(1)_{B-L} gauge groups. Except a complex singlet
scalar for the U(1)_{B-L} symmetry breaking, the other new scalars and fermions
(one scalar doublet, two or more real scalar singlets/triplets and three
right-handed neutrinos) are odd under an unbroken Z_2 discrete symmetry. The
real scalar decays can produce an asymmetry stored in the new scalar doublet
which subsequently decays into the standard model lepton doublets and the
right-handed neutrinos. The lepton asymmetry in the standard model leptons then
can be partially converted to a baryon asymmetry by the sphaleron processes. By
integrating out the heavy scalar singlets/triplets, we can realize an effective
theory to radiatively generate the small neutrino masses at the TeV scale.
Furthermore, the lightest right-handed neutrino can serve as a dark matter
candidate.
