Dynamics of a Persistent Insulator-to-Metal Transition in Strained Manganite Films
Journal
Physical Review Letters
Journal Volume
123
Journal Issue
26
ISSN
00319007
Date Issued
2019-12-30
Author(s)
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 La0.67Ca0.33MnO3, optical excitation with a sub-100-fs pulse above 2 mJ/cm2 leads to a persistent metallic phase below 100 K. Using single-shot optical and terahertz spectroscopy, we show that this phase transition is a multistep 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. © 2019 American Physical Society.
SDGs
Other Subjects
Degrees of freedom (mechanics); Free energy; Manganites; Photoexcitation; Terahertz spectroscopy; Transition metal oxides; Transition metals; Energy landscape; Free energy surface; Insulator-to-metal transitions; Manganite films; Metallic phase; Multistep process; Partial charge ordering; Time-dependent Ginzburg-Landau models; Metal insulator transition; article; melting point; phase transition; terahertz spectroscopy
Type
journal article