English

Dynamical crossover between stretched- and compressed-exponential relaxation in a photoexcited crystal

Strongly Correlated Electrons 2025-09-08 v1 Soft Condensed Matter

Abstract

Anomalous relaxation is one of the hallmarks of disordered systems. Following perturbation by an external source, many glassy, jammed and amorphous systems relax as a stretched or compressed exponential as a function of time. However, despite their ubiquity, the origins of and the connection between these phenomenological relaxation functions remains to be understood. Here, we observe a tunable crossover from stretched- to compressed-exponential relaxation by photoexciting single crystal Ca3Ru2O7 across a structural phase transition. We present a simple lattice model that shows how spatial inhomogeneity and local, strain-mediated interactions cooperate to produce the dynamical crossover. Our work reveals anomalous relaxation dynamics in an idealized single crystal material and establishes photoexcited solids as promising platforms for probing the mechanisms underlying anomalous relaxation.

Keywords

Cite

@article{arxiv.2509.04814,
  title  = {Dynamical crossover between stretched- and compressed-exponential relaxation in a photoexcited crystal},
  author = {Tyler Carbin and Joel Herman and Xinshu Zhang and Adrian B. Culver and Yu Zhang and Hengdi Zhao and Rahul Roy and Gang Cao and Anshul Kogar},
  journal= {arXiv preprint arXiv:2509.04814},
  year   = {2025}
}