Resolving the VO2 controversy: Mott mechanism dominates the insulator-to-metal transition

Article

关键词: CORRELATED MATERIALS;    HUBBARD TRANSITION;    OPTICAL-PROPERTIES;    SUPPRESSION;    OXIDES;   

DOI  :  10.1103/PhysRevB.95.035113

来源: SCIE

【 摘 要 】

We consider a minimal model to investigate the metal-insulator transition in VO2. We adopt a Hubbard model with two orbitals per unit cell, which captures the competition between Mott and singlet-dimer localization. We solve the model within dynamical mean-field theory, 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 with a metallic state characterized by a split heavy quasiparticle band. Our results show that the thermal-driven insulator-to-metal transition in VO2 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.

【 授权许可】

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