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arXiv · 1007.4624

Observation of new intrinsic properties of VO2

Bongjin Simon Mun·Kai Chen·Youngchul Leem·Catherine Dejoie·Nobumichi Tamura·Martin Kunz·Zhi Liu·Michael E. Grass·Changwoo Park·Y. Yvette Lee·Honglyoul Ju
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Abstract

The single crystal VO2, exihibiting a first-order metal-insulator transition (MIT) at 67.2 degrees C and an insulator-insulator transition (IIT) at ~49.7 degrees C, is grown. From synchrotron-based x-ray microdiffraction analysis, the IIT shows structural phase transition (SPT) of monoclinic M2 to M1 phases while the MIT displays M1 to rutile R phases. The IIT exhibits percolative SPT while the MIT shows abrupt transition width of < 0.02 degrees C, supporting Mott's prediction. The MIT occurs non-percolatively with a sharp boundary between R and M1 phases. The MIT onset temperature shows significant variation.

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Bongjin Simon Mun, Kai Chen, Youngchul Leem, Catherine Dejoie, Nobumichi Tamura, Martin Kunz, Zhi Liu, Michael E. Grass, Changwoo Park, Y. Yvette Lee, Honglyoul Ju. 2010-07-27. Observation of new intrinsic properties of VO2. https://arxiv.org/abs/1007.4624

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