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arXiv · 1905.12739

Nucleation and growth bottleneck in the conductivity recovery dynamics of nickelate thin films

Elsa Abreu·Derek Meyers·Verner K. Thorsmolle·Jingdi Zhang·Xiaoran Liu·Kun Geng·Jak Chakhalian·Richard D. Averitt
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Abstract

We investigate THz conductivity dynamics in NdNiO$_3$ and EuNiO$_3$ thin films following a photoinduced thermal quench into the metallic state and reveal a clear contrast between first- and second-order dynamics. While in EuNiO$_3$ the conductivity recovers exponentially, in NdNiO$_3$ the recovery is non-exponential and slower than a simple thermal model. Crucially, it is consistent with first-order dynamics and well-described by a 2d Avrami model, with supercooling leading to metastable phase coexistence. The large transients seen in our films are promising for fast electronic (and magnetic) switching applications.

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Elsa Abreu, Derek Meyers, Verner K. Thorsmolle, Jingdi Zhang, Xiaoran Liu, Kun Geng, Jak Chakhalian, Richard D. Averitt. 2019-05-29. Nucleation and growth bottleneck in the conductivity recovery dynamics of nickelate thin films. https://doi.org/10.1021/acs.nanolett.0c02828

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