Spectral functions and optical conductivity of spinless fermions on a checkerboard lattice

TL;DR

This paper investigates the dynamical properties of spinless fermions on a checkerboard lattice, focusing on spectral functions and optical conductivity in the large repulsion limit, revealing fractional charge excitations and their role in electrical current.

Contribution

It provides new insights into the spectral functions and optical conductivity of spinless fermions, highlighting the impact of fractional charges in the large repulsion regime.

Findings

Spectral functions exhibit broad low-energy excitations due to fractional charges.

Fractional charges significantly contribute to electrical current density.

The study enhances understanding of dynamical properties in strongly interacting fermion systems.

Abstract

We study the dynamical properties of spinless fermions on the checkerboard lattice. Our main interest is the limit of large nearest-neighbor repulsion $V$ as compared with hopping $|t|$. The spectral functions show broad low-energy excitation which are due to the dynamics of fractionally charged excitations. Furthermore, it is shown that the fractional charges contribute to the electrical current density.