Electron-lattice coupling and partial nesting as the origin of Fermi-Arcs in manganites

TL;DR

This study uses Monte Carlo simulations of a tight-binding model to reveal that electron-lattice interactions and partial Fermi surface nesting cause Fermi-arc phenomena in layered manganites, characterized by pseudogap features.

Contribution

It demonstrates that Fermi-arcs originate from electron-lattice coupling and Fermi surface nesting without broken symmetry, providing a microscopic understanding of this phase in manganites.

Findings

Fermi-arcs linked to electron-lattice coupling and nesting.

Spectral weight suppression near Brillouin zone edges.

Pseudogap formation in the density of states.

Abstract

A tight-binding model for eg electrons coupled to Jahn-Teller lattice distortions is studied via unbiased Monte- Carlo simulations. By focusing on the periodicity of the Jahn Teller distortions, and the one-particle spectral function, our results clarify the physical origin of the Fermi-arcs phase observed in layered manganites. In a range of parameters where no broken symmetry phase exists, the nearly nested Fermi surface favors certain correlations between Jahn Teller distortions. The spectral weight near the Brillouin zone edge is suppressed, leading to the pseudogap in the density of states. We discuss the stability of this phase as a function of temperature and coupling strength for different hole dopings.