Asymmetry of the electron spectrum in hole-doped and electron-doped cuprates

TL;DR

This paper investigates the asymmetry in electron spectra between hole-doped and electron-doped cuprates using the t-t'-J model, revealing differences in quasiparticle dispersion and their relation to magnetic excitations.

Contribution

It demonstrates the electron-hole asymmetry in quasiparticle dispersion and links it to strong coupling with magnetic excitations within the t-t'-J model.

Findings

Flat band around (π,0) in both dopings

Lowest energy states differ at (π/2,π/2) and (π,0)

Electron spectrum related to magnetic excitations

Abstract

Within the t-t'-J model, the asymmetry of the electron spectrum and quasiparticle dispersion in hole-doped and electron-doped cuprates is discussed. It is shown that the quasiparticle dispersions of both hole-doped and electron-doped cuprates exhibit the flat band around the (\pi,0) point below the Fermi energy. The lowest energy states are located at the (\pi/2,\pi/2) point for the hole doping, while they appear at the (\pi,0) point in the electron-doped case due to the electron-hole asymmetry. Our results also show that the unusual behavior of the electron spectrum and quasiparticle dispersion is intriguingly related to the strong coupling between the electron quasiparticles and collective magnetic excitations.