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arXiv · 1906.10334

Dynamics of a Persistent Insulator-to-Metal Transition in Strained Manganite Films

Samuel W. Teitelbaum·Benjamin K. Ofori-Okai·Yu-Hsiang Cheng·Jingdi Zhang·Feng Jin·Wenbin Wu·Richard D. Averitt·Keith A. Nelson
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Abstract

Transition metal oxides possess complex free energy surfaces with competing degrees of freedom. Photoexcitation allows shaping of such rich energy landscapes. In epitaxially strained $\mathrm{La_{0.67}Ca_{0.33}MnO_3}$, optical excitation with a sub-100 fs pulse above $2\ \mathrm{mJ/cm^2}$ leads to a persistent metallic phase below 100 K. Using single-shot optical and terahertz spectroscopy, we show that this phase transition is a multi-step process. We conclude that the phase transition is driven by partial charge order melting, followed by growth of the persistent metallic phase on longer timescales. A time-dependent Ginzburg-Landau model can describe the fast dynamics of the reflectivity, followed by longer timescale in-growth of the metallic phase.

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Samuel W. Teitelbaum, Benjamin K. Ofori-Okai, Yu-Hsiang Cheng, Jingdi Zhang, Feng Jin, Wenbin Wu, Richard D. Averitt, Keith A. Nelson. 2019-07-03. Dynamics of a Persistent Insulator-to-Metal Transition in Strained Manganite Films. https://doi.org/10.1103/physrevlett.123.267201

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