Incommensurate charge density wave modulated by period of Hubbard superlattices

Abstract

The charge structure factor of the half-filled Hubbard superlattices with one on-site repulsive site and [Formula: see text] free sites per unit cell is investigated numerically. The behaviors of charge structure reveal a kind of even–odd [Formula: see text] disparity. For even [Formula: see text], we always observe a commensurate charge density wave (CDW). For odd [Formula: see text], we observe a commensurate–incommensurate CDW transition at a critical on-site repulsion around the particle–hole symmetric point. This transition results from the competition between the local charge correlations with odd distance and even distance.