ARPES spectral functions and Fermi surface for La(1.86)Sr(0.14)CuO(4) compared with LDA+DMFT+Sk calculations

TL;DR

This study combines high-resolution ARPES experiments with advanced LDA+DMFT+Sk calculations to analyze the Fermi surface and pseudogap phenomena in underdoped LSCO, revealing Fermi surface destruction and arc formation linked to antiferromagnetic fluctuations.

Contribution

It introduces a combined experimental and computational approach using LDA+DMFT+Sk to accurately model pseudogap effects in high-Tc cuprates, highlighting the AFM origin of Fermi surface anomalies.

Findings

Fermi surface destruction near (pi,0) observed experimentally and theoretically.

Formation of Fermi arcs in the nodal directions confirmed.

Spectral functions indicate pseudogap caused by AFM fluctuations.

Abstract

Slightly underdoped high-Tc system La(1.86)Sr(0.14)CuO(4) (LSCO) is studied by means of high energy high resolution angular resolved photoemission spectroscopy (ARPES) and combined computational scheme LDA+DMFT+Sk. Corresponding one band Hubbard model is solved via dynamical mean-field theory (DMFT), while model parameters needed are obtained from first principles within local density approximation (LDA). An "external" k-dependent self-energy Sk describes interaction of correlated electrons with antiferromagnetic (AFM) pseudogap fluctuations. Experimental and theoretical data clearly show "destruction" of the LSCO Fermi surface in the vicinity of the (pi,0) point and formation of "Fermi arcs" in the nodal directions. ARPES energy distribution curves (EDC) as well as momentum distribution curves (MDC) demonstrate deviation of the quasiparticle band from the Fermi level around (pi,0) point. The same behavior of spectral functions follows from theoretical calculations suggesting AFM origin of the pseudogap state.