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arXiv · 0902.2115

Probing ultrafast symmetry breaking in photo-stimulated matter

Daniele Fausti·Oleg V. Misochko·Paul H. M. van Loosdrecht
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Abstract

The nature of a phase transition is inherently connected to the changes in the crystalline symmtry, which is typically probed by elastic or inelastic scattering with neutrons, electrons or photons. When such a phase transition is stimulated by light or other sudden perturbations the solid evolves along a non-equilibrium pathway of which the underlying physics is poorly understood. Here we use picosecond Raman scattering to study the photo-induced ultrafast dynamics in Peierls distorted Antimony. We find evidence for an ultrafast non-thermal reversible structural phase transition. Most surprisingly, we find evidence that this transition evolves toward a lower symmetry, in contrast to the commonly accepted rhombohedral-to-simple cubic transition path. Our study demonstrates the feasibility of ultrafast Raman scattering symmetry analysis of photo-induced non-thermal transient phases.

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Daniele Fausti, Oleg V. Misochko, Paul H. M. van Loosdrecht. 2009-02-12. Probing ultrafast symmetry breaking in photo-stimulated matter. https://doi.org/10.1103/physrevb.80.161207

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