Hole Dopants Disentangling Peierls-Mott Relevance States of VO2 by First-Principles Calculation

The formation mechanism of the metastable M-2-phase VO2, which is believed to be a true Mott insulator, has attracted great attention for understanding the intriguing physics of the metal-insulator transition of VO2 and the promising application in ultrafast electronic switching devices. Herein, we conducted the hole-doping calculation regardless of the type of element and revealed theoretically that the hole carriers disentangle the complex Mott-Peierls relevance states of M-1-phase VO2. The hole induces the zigzag dimerized V-V chains to separate into two different states: one remains paired but straight and the other remains zigzag but unpaired. The dedimerization weakens the intradimer hopping, which makes the superexchange interaction come into effect, consequently resulting in the formation of the spin antiferromagnetic ordering along the zigzag unpaired V-V chains, indicating that the Mott correlation plays a dominant role in the formation of M-2-VO2. This work gives an insight into the mechanism of stabilizing the true Mott insulator M-2-VO2, which would offer an opportunity for the realization of Mott transition field-effect transistors.

Automated summary

Hole doping changes the electronic structure of VO2, leading to the dedimerization of the Mott-Peierls related states and the formation of M-2-VO2. This finding provides important insights for the development of Mott transition field-effect transistors.