Non-monotonic Fermi surface evolution and its correlation with stripe ordering in bilayer manganites

TL;DR

This study reveals how Fermi surface evolution in bilayer manganites correlates with stripe ordering, showing that different stripe types are linked to specific Fermi surface features and that doping induces significant electronic property changes.

Contribution

It uncovers the relationship between Fermi surface topology and stripe order types in bilayer manganites using ARPES measurements across doping levels.

Findings

One stripe type links to nested Fermi surface regions.

Another stripe type aligns with the real space lattice but can be Fermi surface driven.

Fermi surface deviations at certain dopings lead to unusual electronic behaviors.

Abstract

In correlated electron systems such as cuprate superconductors and colossal magnetoresistive (CMR) oxides there is often a tendency for a nanoscale self-organization of electrons that can give rise to exotic properties and to extreme non-linear responses. The driving mechanisms for this self-organization are highly debated, especially in the CMR oxides in which two types of self-organized stripes of charge and orbital order coexist with each other. By utilizing angle-resolved photoemission spectroscopy measurements over a wide doping range, we show that one type of stripe is exclusively linked to long flat portions of nested Fermi surface, while the other type prefers to be commensurate with the real space lattice but also may be driven away from this by the Fermi surface. Complementarily, the Fermi surface also appears to be driven away from its non-interacting value at certain doping levels, giving rise to a host of unusual electronic properties.