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arXiv · 1903.00464

Metal-insulator transition in quasi-one-dimensional HfTe3 in the few-chain limit

Scott Meyer·Thang Pham·Sehoon Oh·Peter Ercius·Christian Kisielowski·Marvin L. Cohen·Alex Zettl
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Abstract

The quasi-one-dimensional linear chain compound HfTe3 is experimentally and theoretically explored in the few- to single-chain limit. Confining the material within the hollow core of carbon nanotubes allows isolation of the chains and prevents the rapid oxidation which plagues even bulk HfTe3. High-resolution transmission electron microscopy combined with density functional theory calculations reveals that, once the triple-chain limit is reached, the normally parallel chains spiral about each other, and simultaneously a short-wavelength trigonal anti-prismatic rocking distortion occurs that opens a significant energy gap. This results in a size-driven metal-insulator transition.

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Scott Meyer, Thang Pham, Sehoon Oh, Peter Ercius, Christian Kisielowski, Marvin L. Cohen, Alex Zettl. 2019-03-01. Metal-insulator transition in quasi-one-dimensional HfTe3 in the few-chain limit. https://doi.org/10.1103/physrevb.100.041403

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