Doping evolution of the electronic structure in the single-layer cuprates Bi$_2$Sr$_{2-x}$La$_x$CuO$_{6+\delta}$: Comparison with other single-layer cuprates

TL;DR

This study investigates the doping-dependent electronic structure evolution in single-layer cuprate Bi2201, revealing similarities with Na-CCOC and differences from LSCO, through ARPES and core-level XPS measurements.

Contribution

It provides a detailed comparison of doping evolution in Bi2201 with other cuprates, highlighting the role of chemical potential shifts and band structure changes.

Findings

Doping induces formation of dispersive quasiparticle bands and Fermi arcs.

Bi2201's doping behavior resembles Na-CCOC with a rapid chemical potential shift.

Distinct from LSCO, where the chemical potential remains fixed despite doping.

Abstract

We have performed angle-resolved photoemission and core-level x-ray photoemission studies of the single-layer cuprate Bi$_2$Sr$_{2-x}$La$_x$CuO$_{6+\delta}$ (Bi2201) and revealed the doping evolution of the electronic structure from the lightly-doped to optimally-doped regions. We have observed the formation of the dispersive quasi-particle band, evolution of the Fermi ``arc'' into the Fermi surface and the shift of the chemical potential with hole doping as in other cuprates. The doping evolution in Bi2201 is similar to that in Ca$_{2-x}$Na$_{x}$CuO$_{2}$Cl$_2$ (Na-CCOC), where a rapid chemical potential shift toward the lower Hubbard band of the parent insulator has been observed, but is quite different from that in La$_{2-x}$Sr$_{x}$CuO$_{4}$ (LSCO), where the chemical potential does not shift, yet the dispersive band and the Fermi arc/surface are formed around the Fermi level already in the lightly-doped region. The (underlying) Fermi surface shape and band dispersions are quantitatively analyzed using tight-binding fit, and the deduced next-nearest-neighbor hopping integral $t'$ also confirm the similarity to Na-CCOC and the difference from LSCO.