Momentum-space electronic structures and charge orders of high-temperature superconductors Ca2-xNaxCuO2Cl2 and Bi2Sr2CaCu2O8+delta

TL;DR

This study investigates the electronic structures and charge orders in high-temperature superconductors Ca2-xNaxCuO2Cl2 and Bi2Sr2CaCu2O8+delta across various doping levels using ARPES, revealing that charge order is likely driven by strong correlations rather than Fermi surface nesting.

Contribution

It provides a comprehensive ARPES analysis of the doping-dependent Fermi surface and charge order, challenging the idea that FS nesting causes charge order in these materials.

Findings

Nesting wave vector decreases monotonically with doping.

Charge order pattern does not correlate with Fermi surface nesting.

Charge order likely originates from strong correlation effects.

Abstract

We study the electronic structure of Ca2-xNaxCuO2Cl2 and Bi2Sr2CaCu2O8+d samples in a wide range of doping, using angle-resolved photoemission spectroscopy, with emphasis on on the Fermi surface (FS) in the near anti-nodal region. The "nesting wave vector", i.e., the wave vector that connects two nearly flat pieces of the Fermi surface in the anti-nodal region, reveals a universal monotonic decrease in magnitude as a function of doping. Comparing our results to the charge order recently observed by scanning tunneling spectroscopy (STS), we conclude that the FS nesting and the charge order pattern seen in STS do not have a direct relationship. Therefore,the charge order likely arises due to strong correlation physics rather than FS nesting physics.