Visualization of defects in single-crystal and thin-film PdCoO2 using aberration-corrected scanning transmission electron microscopy
Date
02/09/2022Metadata
Show full item recordAbstract
Single-crystal delafossite PdCoO2 is known to have an extremely low intrinsic impurity concentration of ~0.001%, demonstrating extraordinarily high conductivity with a mean free path of ~20 microns at low temperatures. However, when grown as thin films, the resistivity at room temperature increases by a factor of 3 to 80 times, depending on the film thickness. Using scanning transmission electron microscopy, we identify different classes of defects for the single crystal vs epitaxial thin film. The dominant defect for single-crystal PdCoO2 is found to be ribbon-like defects. For the thin films, we identify different types of defects arising in epitaxial thin films mainly due to substrate termination that disrupt the lateral connectivity of the conducting planes. Our results are consistent with the high conductivity of single crystals and increased electrical resistivity of the thin films compared to that of single crystals, suggesting that selecting a proper substrate, improving surface quality, and reducing the step density are the keys to enhance the film quality for utilizing PdCoO2 as a platform for future applications.
Citation
Chang , C , Sun , J , Khim , S , Mackenzie , A , Schlom , D & Muller , D 2022 , ' Visualization of defects in single-crystal and thin-film PdCoO 2 using aberration-corrected scanning transmission electron microscopy ' , Physical Review Materials , vol. 6 , 093401 . https://doi.org/10.1103/PhysRevMaterials.6.093401
Publication
Physical Review Materials
Status
Peer reviewed
ISSN
2475-9953Type
Journal article
Rights
Copyright © 2022 American Physical Society. This work has been made available online in accordance with publisher policies or with permission. Permission for further reuse of this content should be sought from the publisher or the rights holder. This is the author created accepted manuscript following peer review and may differ slightly from the final published version. The final published version of this work is available at https://journals.aps.org/prmaterials/
Description
Funding: This work was primarily supported by the U.S. Department of Energy, Office of Basic Sciences, Division of Materials Sciences and Engineering, under Award No. DE-SC0002334.Collections
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