Dimensionality-driven metal–insulator transition in spin–orbit-coupled IrO2

DOI: 10.1039/D1NR04207F

Authors: E. Arias-Egido (Universidad de Zaragoza; Instituto de Ciencia de Materiales de Madrid, CSIC) , M. A. Laguna-Marco (Instituto de Nanociencia y Materiales de Aragón (INMA), CSIC - Universidad de Zaragoza) , C. Piquer (Instituto de Nanociencia y Materiales de Aragón (INMA), CSIC - Universidad de Zaragoza) , P. Jimenez-Cavero (Instituto de Nanociencia y Materiales de Aragón (INMA), CSIC - Universidad de Zaragoza) , I. Lucas (Instituto de Nanociencia y Materiales de Aragón (INMA), CSIC - Universidad de Zaragoza) , L. Morellon (Instituto de Nanociencia y Materiales de Aragón (INMA), CSIC - Universidad de Zaragoza) , F. Gallego (GFMC, Universidad Complutense de Madrid) , A. Rivera-Calzada (GFMC, Universidad Complutense de Madrid) , M. Cabero (ICTS - Centro Nacional de Microscopía Electrónica, Universidad Complutense de Madrid) , J. Santamaría (GFMC, Universidad Complutense de Madrid; Unidad Asociada UCM/CSIC;) , G. Fabbris (Advanced Photon Source) , D. Haskel (Advanced Photon Source) , R. Boada (Universitat Autonoma de Barcelona; Diamond Light Source) , S. Diaz-Moreno (Diamond Light Source)
Co-authored by industrial partner: No

Type: Journal Paper
Journal: Nanoscale

State: Published (Approved)
Published: October 2021
Diamond Proposal Number(s): 17266

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.

Subject Areas: Physics, Materials


Instruments: I20-Scanning-X-ray spectroscopy (XAS/XES)

Added On: 13/10/2021 10:35

Documents:
d1nr04207f.pdf

Discipline Tags:

Surfaces Physics Magnetism Materials Science interfaces and thin films

Technical Tags:

Spectroscopy X-ray Absorption Spectroscopy (XAS) High Energy Resolution Fluorescence Detected XAS (HERFD-XAS)