Magnetic excitations in stripe-ordered La$_{1.875}$Ba$_{0.125}$CuO$_4$ studied using resonant inelastic x-ray scattering

TL;DR

This study uses resonant inelastic x-ray scattering to investigate charge and spin correlations in stripe-ordered La$_{1.875}$Ba$_{0.125}$CuO$_4$, finding that static charge order does not significantly alter the paramagnon excitations compared to other cuprates.

Contribution

First RIXS study to measure charge and spin excitations in stripe-ordered La$_{1.875}$Ba$_{0.125}$CuO$_4$, revealing minimal impact of static charge order on paramagnon dispersion.

Findings

Static charge order observed at (0.24, 0) wavevector.

Paramagnon dispersion similar to other cuprates without static charge order.

No significant change in magnetic excitations due to charge order within experimental uncertainty.

Abstract

The charge and spin correlations in La$_{1.875}$Ba$_{0.125}$CuO$_4$ (LBCO 1/8) are studied using Cu $L_3$ edge resonant inelastic x-ray scattering (RIXS). The static charge order (CO) is observed at a wavevector of $(0.24,0)$ and its charge nature confirmed by measuring the dependence of this peak on the incident x-ray polarization. The paramagnon excitation in LBCO 1/8 is then measured as it disperses through the CO wavevector. Within the experimental uncertainty no changes are observed in the paramagnon due to the static CO, and the paramagnon seems to be similar to that measured in other cuprates, which have no static CO. Given that the stripe correlation modulates both the charge and spin degrees of freedom, it is likely that subtle changes do occur in the paramagnon due to CO. Consequently, we propose that future RIXS measurements, realized with higher energy resolution and sensitivity, should be performed to test for these effects.