  Photo-excited charge dynamics of interacting charge-frustrated systems are
studied using a spinless fermion model on an anisotropic triangular lattice.
Real-time evolution of the system after irradiating a pump-photon pulse is
analyzed by the exact diagonalization method. We focus on photo-excited states
in the two canonical charge-ordered (CO) ground states, i.e., horizontal
stripe-type and vertical stripe-type COs, which compete with each other owing
to the charge frustration. We find that the photo-induced excited states from
the two types of COs are distinct. From the horizontal stripe-type CO, a
transition to another CO state called the three-fold CO phase occurs. In sharp
contrast, the vertical stripe-type CO phase is only weakened by
photo-irradiation. Our observations are attributable to the charge frustration
effects occurring in the photo-excited states.
