Homogeneous versus glassy, phase-separated character with respect to orbital order

Determine whether the photo-induced phase in La2/3Ca1/3MnO3 is a homogeneous state with reduced orbital order or a glassy, phase-separated configuration by directly resolving orbital-order superstructures and distinguishing between these possibilities.

Background

The interplay of charge, orbital order, and Jahn-Teller distortions is central to manganites. The authors propose that photo-excitation may disrupt long-range orbital/charge order while only partially reducing local Jahn-Teller distortions, potentially yielding a disordered or glassy state.

However, their O K-edge RIXS measurements provide volume-averaged information and lack sensitivity to orbital-order superlattice peaks, preventing an unambiguous determination of whether the photo-induced state is homogeneous or glassy/phase-separated. They note that time-resolved resonant x-ray diffraction at the Mn L-edge would be needed.

References

At the same time, because our O $K$-edge RIXS measurements do not directly resolve orbital-order superlattice peaks and provide only volume-averaged information, we cannot distinguish unambiguously between a homogeneous phase with reduced orbital order and a more glassy, phase-separated configuration.

— Excitations across the equilibrium and photoinduced `hidden' states of magnetoresistive manganites  (2604.00991 - Fan et al., 1 Apr 2026) in Discussion