Abstract

We present a numerical study of the charge dynamical structure factor N(k,omega) of a one-dimensional (1D) ionic Hubbard model in the Mott insulator phase. We show that the low-energy spectrum of N(k,omega) is expressed in terms of the spin operators for the spin degrees of freedom. Numerical results of N(k,omega) for the spin degrees of freedom, obtained by the Lanczos diagonalization method, well reproduce the low-energy spectrum of N(k,omega) of the 1D ionic Hubbard model. In addition, we show that these spectral peaks probe the dispersion of the spin-singlet excitations of the system and are observed in the wide parameter region of the MI phase.

Full Text
Published version (Free)

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call