  The dynamical mean-field theory is employed to study the orbital-selective
Mott transition (OSMT) of the two-orbital Hubbard model with nearest neighbor
hopping and next-nearest neighbor (NNN) hopping. The NNN hopping breaks the
particle-hole symmetry at half filling and gives rise to an asymmetric density
of states (DOS). Our calculations show that the broken symmetry of DOS benefits
the OSMT, where the region of the orbital-selective Mott phase significantly
extends with the increasing NNN hopping integral. We also find that Hund's rule
coupling promotes OSMT by blocking the orbital fluctuations, but the influence
of NNN hopping is more remarkable.
