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

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.

includes supplemental material