Probing the interplay between lattice dynamics and short-range magnetic correlations in CuGeO3 with femtosecond RIXS

TL;DR

This study demonstrates how femtosecond time-resolved RIXS can probe short-range magnetic correlations and their coupling to lattice dynamics in CuGeO3, a spin-frustrated material, revealing insights into non-long-range magnetic excitations.

Contribution

The paper introduces the use of time-resolved RIXS at the O K-edge to investigate short-range magnetic correlations in a frustrated spin chain, combining experimental data with model calculations.

Findings

Detection of short-range spin correlations via trRIXS

Observation of strong coupling between lattice and spin subsystems

Probing magnetic dynamics in the absence of long-range order

Abstract

Investigations of magnetically ordered phases on the femtosecond timescale have provided significant insights into the influence of charge and lattice degrees of freedom on the magnetic sub-system. However, short-range magnetic correlations occurring in the absence of long-range order, for example in spin-frustrated systems, are inaccessible to many ultrafast techniques. Here, we show how time-resolved resonant inelastic X-ray scattering (trRIXS) is capable of probing such short-ranged magnetic dynamics in a charge-transfer insulator through the detection of a Zhang-Rice singlet exciton. Utilizing trRIXS measurements at the O K-edge, and in combination with model calculations, we probe the short-range spin-correlations in the frustrated spin chain material CuGeO3 following photo-excitation, revealing a strong coupling between the local lattice and spin sub-systems.