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arXiv · 1411.4532

Direct Observation of Decoupled Structural and Electronic Transitions and an Ambient Pressure Monoclinic-Like Metallic Phase of VO$_2$

J. Laverock·S. Kittiwatanakul·A. A. Zakharov·Y. R. Niu·B. Chen·S. A. Wolf·J. W. Lu·K. E. Smith
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Abstract

We report the simultaneous measurement of the structural and electronic components of the metal-insulator transition of VO$_2$ using electron and photoelectron spectroscopies and microscopies. We show that these evolve over different temperature scales, and are separated by an unusual monoclinic-like metallic phase. Our results provide conclusive evidence that the new monoclinic-like metallic phase, recently identified in high-pressure and nonequilibrium measurements, is accessible in the thermodynamic transition at ambient pressure, and we discuss the implications of these observations on the nature of the MIT in VO$_2$.

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J. Laverock, S. Kittiwatanakul, A. A. Zakharov, Y. R. Niu, B. Chen, S. A. Wolf, J. W. Lu, K. E. Smith. 2014-11-17. Direct Observation of Decoupled Structural and Electronic Transitions and an Ambient Pressure Monoclinic-Like Metallic Phase of VO$_2$. https://doi.org/10.1103/physrevlett.113.216402

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