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Research & Reviews: Journal of Material Sciences | ISSN: 2321-6212 | Volume 6
Theoretical, Materials and Condensed Matter Physics
5
th
International Conference on
November 26-28, 2018 | Los Angeles, USA
Resolving the VO
2
controversy: Mott mechanism dominates the insulator-to-metal transition
V Dobrosavljevic
Florida State University, USA
W
e consider a minimal model to investigate the metal-insulator transition in VO
2
. We adopt a Hubbard model with two orbital
per unit cell, which captures the competition between Mott and singlet-dimer localization. We solve the model within
Dynamical Mean FieldTheory, characterizing in detail the metal-insulator transition and finding new features in the electronic states.
We compare our results with available experimental data obtaining good agreement in the relevant model parameter range. Crucially,
we can account for puzzling optical conductivity data obtained within the hysteresis region, which we associate to a novel metallic
state characterized by a split heavy quasiparticle band. Our results show that the thermal-driven insulator-to-metal transition in VO
2
is compatible with a Mott electronic mechanism, providing fresh insight to a long-standing “chicken-and-egg” debate and calling for
further research of “Mottronics” applications of this system. Notably, we find Hubbard bands of a mixed character with coherent and
incoherent excitations. We argue that this state is relevant for VO
2
and its signatures may be observed in spectroscopic studies, and
possibly through pump-probe experiments.
vlad@magnet.fsu.eduRes. Rev. J Mat. Sci. 2018, Volume 6
DOI: 10.4172/2321-6212-C10-042