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arXiv · 1112.1573

VO2 nanosheets: controlling the THz properties through strain engineering

Elsa Abreu·Mengkun Liu·Jiwei Lu·Kevin G. West·Salinporn Kittiwatanakul·Wenjing Yin·Stuart A. Wolf·Richard D. Averitt
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Abstract

We investigate far-infrared properties of strain engineered vanadium dioxide nanosheets through epitaxial growth on a (100)R TiO2 substrate. The nanosheets exhibit large uniaxial strain leading to highly uniform and oriented cracks along the rutile c-axis. Dramatic anisotropy arises for both the metal-insulator transition temperature, which is different from the structural transition temperature along the cR axis, and the metallic state conductivity. Detailed analysis reveals a Mott-Hubbard like behavior along the rutile cR axis.

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Elsa Abreu, Mengkun Liu, Jiwei Lu, Kevin G. West, Salinporn Kittiwatanakul, Wenjing Yin, Stuart A. Wolf, Richard D. Averitt. 2011-12-07. VO2 nanosheets: controlling the THz properties through strain engineering. https://doi.org/10.1088/1367-2630%2F14%2F8%2F083026

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