Fermi Surface Reconstruction in Underdoped Cuprates: The Origin of Electron Pockets

TL;DR

This paper presents a phenomenological model explaining Fermi surface reconstruction in underdoped cuprates, attributing electron pocket formation to strong correlations and charge density wave effects, aligning with experimental observations.

Contribution

It introduces a model combining the $t-J$ framework with charge density wave effects to explain Fermi surface evolution and electron pocket emergence in underdoped cuprates.

Findings

Fermi surface reconstructs into electron pockets due to charge density wave.

Transition to CDW phase occurs at doping level ~0.08 with diverging effective mass.

Hall and Seebeck coefficients change sign at the transition.

Abstract

A new phenomenological model is proposed to describe the evolution of the Fermi surface (FS) in a wide range of dopings. It reproduces the key features of the cuprates in the underdoped phase above the superconducting temperature $T_c$. It is shown that the explicit accounting of strong electron correlation in the framework of the $t-J$ model taken in complementary to the translational symmetry breaking induced by the charge density wave (CDW) gives rise to the Fermi surface reconstruction (FSR) into small electron pockets. While the strong Coulomb repulsion leads to an emergence of the arc-like Fermi surface in the pseudogap (PG) phase, the Bragg reflection on the boundaries of the reduced Brillouin zone (BZ) opens up a possibility to close the quasiparticle orbits. Direct calculation of the FS properties allows us to unveil the scenario of the experimentally observed transition to the CDW phase that sets in at the doping level $\delta\approx0.08$ and is accompanied by a divergence of the carriers effective mass and the sign reversals of the Hall and Seebeck coefficients.