Ultrafast surface melting of orbital order in La0.5Sr1.5MnO4
arXiv:2407.03013 · doi:10.1038/s41563-025-02379-4
Abstract
Understanding how light modifies long-range order in quantum materials is key to improving our ability to control functionality. However, this is challenging if the response is heterogeneous. Here we address the most common form of light-induced heterogeneity, surface melting, and measure the dynamics of orbital order in the layered manganite, La0.5Sr1.5MnO4. We isolate the surface dynamics from the bulk by measuring the orbital truncation rod as well as orbital Bragg peak. After photoexcitation, the orbital Bragg peak shows an unusual narrowing, which suggests an increase in the correlation length in the probed volume. In contrast, the correlation length at the surface decreases. These differences can be reconciled if the material is heterogeneous, and light melts a less ordered surface. By isolating the surface response, we determine that the loss of long-range order is an incoherent process, which is likely accompanied by the formation of local polarons.
References in corpus (15)
- Nonlinear lattice dynamics as a basis for enhanced superconductivity in YBa2Cu3O6.5
- Origin of band gaps in 3d perovskite oxides
- Visualization of Dynamic Polaronic Strain Fields in Hybrid Lead Halide Perovskites
- Phase Fluctuations and the Absence of Topological Defects in Photo-excited Charge Ordered Nickelate
- Optical manipulation of electronic dimensionality in a quantum material
- Breaking symmetry with light: photo-induced chirality in a non-chiral crystal
- Direct visualization of polaron formation in the thermoelectric SnSe
- Ultrafast lattice disordering can be accelerated by electronic collisional forces
- All-optical seeding of a light-induced phase transition with correlated disorder
- Multi-mode excitation drives disorder during the ultrafast melting of a C4-symmetry-broken phase
- Fluctuation control of non-thermal orbital order
- Ultrafast loss of lattice coherence in the light-induced structural phase transition of VO
- Dynamical decoding of the competition between charge density waves in a kagome superconductor
- Metastability in Coexisting Competing Orders
- Nonthermal order by disorder