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arXiv · 2305.05220

Evidence for bootstrap percolation dynamics in a photo-induced phase transition

Tyler Carbin·Xinshu Zhang·Adrian B. Culver·Hengdi Zhao·Alfred Zong·Rishi Acharya·Cecilia J. Abbamonte·Rahul Roy·Gang Cao·Anshul Kogar
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Abstract

Upon intense femtosecond photo-excitation, a many-body system can undergo a phase transition through a non-equilibrium route, but understanding these pathways remains an outstanding challenge. Here, we use time-resolved second harmonic generation to investigate a photo-induced phase transition in Ca$_3$Ru$_2$O$_7$ and show that mesoscale inhomogeneity profoundly influences the transition dynamics. We observe a marked slowing down of the characteristic time, $\tau$, that quantifies the transition between two structures. $\tau$ evolves non-monotonically as a function of photo-excitation fluence, rising from below 200~fs to $\sim$1.4~ps, then falling again to below 200~fs. To account for the observed behavior, we perform a bootstrap percolation simulation that demonstrates how local structural interactions govern the transition kinetics. Our work highlights the importance of percolating mesoscale inhomogeneity in the dynamics of photo-induced phase transitions and provides a model that may be useful for understanding such transitions more broadly.

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Tyler Carbin, Xinshu Zhang, Adrian B. Culver, Hengdi Zhao, Alfred Zong, Rishi Acharya, Cecilia J. Abbamonte, Rahul Roy, Gang Cao, Anshul Kogar. 2023-05-09. Evidence for bootstrap percolation dynamics in a photo-induced phase transition. https://doi.org/10.1103/physrevlett.130.186902

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