The Fermi surface and the role of electronic correlations in Sm$_{2-x}$Ce$_{x}$CuO$_4$

TL;DR

This study uses a hybrid computational scheme to analyze how electronic correlations influence the band structure and Fermi surface topology in electron-doped Sm$_{2-x}$Ce$_{x}$CuO$_4$, comparing results with experimental observations.

Contribution

It introduces a combined LDA+GTB approach with NMTO-derived parameters to study doping-dependent electronic structure in this high-$T_c$ superconductor.

Findings

Fermi surface topology varies with magnetic order regime.

Electronic correlations significantly affect band dispersion.

Results align with recent experimental data.

Abstract

Using LDA+GTB (local density approximation+generalized tight-binding) hybrid scheme we investigate the band structure of the electron-doped high-$T_c$ material Sm$_{2-x}$Ce$_{x}$CuO$_4$. Parameters of the minimal tight-binding model for this system (the so-called 3-band Emery model) were obtained within the NMTO ($N$-th order Muffin-Tin orbital) method. Doping evolution of the dispersion and Fermi surface in the presence of electronic correlations was investigated in two regimes of magnetic order: short-range (spin-liquid) and long-range (antiferromagnetic metal). Each regime is characterized by the specific topologies of the Fermi surfaces and we discuss their relation to recent experimental data.