Nano Lett
Unité Mixte de Physique, CNRS, Thales, Univ. Paris-Sud, Université Paris-Saclay, 91767 Palaiseau , France.
Published: November 2019
Competition between coexisting electronic phases in first-order phase transitions can lead to a sharp change in the resistivity as the material is subjected to small variations in the driving parameter, for example, the temperature. One example of this phenomenon is the metal-insulator transition (MIT) in perovskite rare-earth nickelates. In such systems, reducing the transport measurement area to dimensions comparable to the domain size of insulating and metallic phases around the MIT should strongly influence the shape of the resistance-temperature curve. Here we measure the temperature dependence of the local resistance and the nanoscale domain distribution of NdNiO areas between Au contacts gapped by 40-260 nm. We find that a sharp resistance drop appears below the bulk MIT temperature at ∼105 K, with an amplitude inversely scaling with the nanogap width. By using X-ray photoemission electron microscopy, we directly correlate the resistance drop to the emergence and distribution of individual metallic domains at the nanogap. Our observation provides useful insight into percolation at the MIT of rare-earth nickelates.
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http://dx.doi.org/10.1021/acs.nanolett.9b02815 | DOI Listing |
Nano Lett
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Department of Materials Science and Engineering, Cornell University, Ithaca, New York 14853, United States.
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Department of Materials Science and Engineering, Seoul National University, Seoul, 08826, Republic of Korea.
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Micro- and Nanosystems, Department of Electrical Engineering, KU Leuven, Kasteelpark Arenberg 10, 3001, Leuven, Belgium.
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Department of Physics, Emory University, Atlanta, Georgia 30322, United States.
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September 2024
Center for Theoretical Physics of Complex Systems, Institute for Basic Science (IBS), 34126, Daejeon, Republic of Korea.
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