Mechanism and observation of Mott transition in VO₂-based two- and three-terminal devices

An abrupt Mott metal-insulator transition (MIT) rather than the continuous MIT near a critical on-site Coulomb energy U/U_c=1 is observed for the time in VO_2, a strongly correlated material, by inducing holes of about0.018% into the conduction band. As a result, a discontinuous jump of the of states on the Fermi surface is observed and inhomogeneity inevitably. The gate effect in fabricated transistors is clear evidence that the MIT is induced by the excitation of holes.