Stabilization of three-dimensional charge order through interplanar orbital hybridization in Pr$_x$Y$_{1-x}$Ba$_2$Cu$_3$O$_{6+\delta}$

TL;DR

This study demonstrates that interplanar orbital hybridization, facilitated by Pr substitution, stabilizes three-dimensional charge order in cuprates, revealing a new pathway to control electronic phases in layered correlated oxides.

Contribution

The paper introduces a method to control electronic phases via interplanar orbital hybridization, using resonant x-ray scattering and calculations in Pr-substituted YBa2Cu3O7.

Findings

Pr substitution induces 3D charge order

Interplanar orbital hybridization acts as a bridge

Control over electronic phases achieved

Abstract

The shape of 3$d$-orbitals often governs the electronic and magnetic properties of correlated transition metal oxides. In the superconducting cuprates, the planar confinement of the $d_{x^2-y^2}$ orbital dictates the two-dimensional nature of the unconventional superconductivity and a competing charge order. Achieving orbital-specific control of the electronic structure to allow coupling pathways across adjacent planes would enable direct assessment of the role of dimensionality in the intertwined orders. Using Cu-$L_3$ and Pr-$M_5$ resonant x-ray scattering and first-principles calculations, we report a highly correlated three-dimensional charge order in Pr-substituted YBa$_2$Cu$_3$O$_{7}$, where the Pr $f$-electrons create a direct orbital bridge between CuO$_2$ planes. With this, we demonstrate that interplanar orbital engineering can be used to surgically control electronic phases in correlated oxides and other layered materials.