The influence of out-of-plane disorder on the formation of pseudogap and Fermi arc in Bi2Sr2-xRxCuOy (R=La and Eu)

TL;DR

This study shows that increasing out-of-plane disorder in Bi2Sr2-xRxCuOy reduces the Fermi arc length and stabilizes the pseudogap, which correlates with suppressed superconductivity.

Contribution

It provides new insights into how out-of-plane disorder affects pseudogap formation and Fermi arc evolution in cuprate superconductors.

Findings

Fermi arc length decreases with more out-of-plane disorder

Out-of-plane disorder stabilizes the antinodal pseudogap

Superfluid density and Tc are suppressed by disorder

Abstract

We found that the length of the Fermi arc decreases with increasing out-of-plane disorder by performing angle resolved photoemission spectroscopy (ARPES) measurements in the superconducting state of optimally doped R=La and Eu samples of Bi2Sr2−xRxCuOy. Since out-of-plane disorder stabilizes the antinodal pseudogap as was shown in our previous study of the normal state, the present results indicate that this antinodal pseudogap persists into the superconducting state and decreases the Fermi arc length. We think that the shrinkage of the Fermi arc reduces the superfluid density, which explains the large suppression of the superconducting transition temperature when out-of-plane disorder is increased.