On Chemical Potential of a Generalized Hubbard Model with Correlated Hopping at Half-Filling

TL;DR

This paper investigates the chemical potential in a generalized Hubbard model with correlated hopping at half-filling, revealing temperature-dependent behavior and phase-dependent differences, highlighting the impact of correlated hopping.

Contribution

It introduces a generalized mean-field approach to analyze the chemical potential, capturing exact results for special cases and exploring temperature effects and phase transitions.

Findings

Chemical potential depends on hopping parameters and temperature.

Kink in chemical potential at metal-insulator transition disappears at higher temperatures.

Correlated hopping significantly influences the chemical potential behavior.

Abstract

In the present paper we study chemical potential of a generalized Hubbard model with correlated hopping at half-filling using a generalized mean-field approximation. For the special case of the model the approach reproduces the exact results: metal-insulator transition, ground state energy. Chemical potential of generelized Hubbard model with correlated hoppig as function of hopping integrals at zero temperature is found. It is shown that chemical potential of the model is temperature-dependent. The dependences of chemical potential of a generalized Hubbard model with correlated hopping on the model parameters are different in metallic and insulating phases leading to a kink at the point of metal-insulator transition in the ground state. With the increase of temperature the kink in the chemical potential curve disappears. The obtained results differ from those of the Hubbard model indicating the important role of correlated hopping.