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Updated: Oct 17, 2025

Author Spotlight: Magnetometric Characterization of Intermediates in the Solid-State Electrochemistry of Redox-Active Metal-Organic Frameworks
Published on: June 9, 2023
Dimensionality-driven metal-insulator transition in spin-orbit-coupled IrO2
E Arias-Egido1,2, M A Laguna-Marco1,2,3, C Piquer1,2
1Instituto de Nanociencia y Materiales de Aragón (INMA), CSIC - Universidad de Zaragoza, Zaragoza 50009, Spain. anlaguna@unizar.es.
Abstract:
A metal-insulator transition is observed in spin-orbit-coupled IrO2 thin films upon reduction of the film thickness. In the epitaxially grown samples, the critical thickness (t ∼ 1.5-2.2 nm) is found to depend on growth orientation (001), (100) or (110). Interestingly from the applied point of view, the insulating behavior is found even in polycrystalline ultrathin films. By analyzing the experimental electrical response with various theoretical models, we find good fits to the Efros-Shklovskii-VRH and the Arrhenius-type behaviors, which suggests an important role of electron correlations in determining the electrical properties of IrO2. Our magnetic measurements also point to a significant role of magnetic order. Altogether, our results would point to a mixed Slater- and Mott-type of insulator.
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