Dynamical properties of interacting charge system on frustrated lattices

Dynamical properties in interacting fermion systems on geometrically frustrated lattices are introduced. As a minimal model for the electronic charge order phenomena, we adopt the so-called spin-less fermion V–tV–t model where the hoppings and interactions of spin-less fermions are taken into account in frustrated lattices. By analyzing this model, we examine (1) dielectric and optical properties in a double triangular lattice, (2) a collective excitation in a dimer-molecular system on a triangular lattice, and (3) a photo-excited state in a triangular lattice. We demonstrate that frustration effects influence directly dynamical properties in these charge systems, and explain successfully recent some experimental results.