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The Insulator-Metal-Transition adjoined by a structural transition of VO2 is induced above room temperature (340 K) by heating or self-heating. A steep resistance-jump of up to five orders of magnitude occurs at this transition in high quality, unstrained single crystals. Insulating domains sliding in the sense of the electric current within the metallic background were found so far exclusively in the current induced mixed metal-insulator phase of VO2 single crystals; it is known for a long time that their uniformity and speed as function of current density are very sensitive to crystal quality. The high energetical cost of domain emission is the focus of our present investigations. In this Communication we report on the surprising behavior of a needle-like VO2 single crystal. Several I-V closed loops traced at room temperature concurrently with video recording of the crystal under the microscope, were followed by R(T) measurements during three slow heating-cooling cycles between room temperature and above 340 K, followed in their turn by an additional set of I-V measurements and video recordings. The results show that the slow cycling through the transition using external heat had a healing effect on the reproducibility of R(T) while increasing the activation energy of conduction in the insulating state and in reducing the damping term in the domains sliding velocity. The intriguing result of this set of measurements was that the energy cost of the domain emission, was higher after healing than prior to it.
Metal-insulator (MI) transitions in correlated electron systems have long been a central and controversial issue in material science. Vanadium dioxide (VO2) exhibits a first-order MI transition at 340 K. For more than half a century, it has been deba
VO2 is a strongly correlated material, which undergoes a reversible metal insulator transition (MIT) coupled to a structural phase transition upon heating (T= 67{deg} C). Since its discovery the nature of the insulating state has long been debated an
Spatial phase inhomogeneity at the nano- to microscale is widely observed in strongly-correlated electron materials. The underlying mechanism and possibility of artificially controlling the phase inhomogeneity are still open questions of critical imp
We present a theoretical investigation of the electronic structure of rutile (metallic) and M$_1$ and M$_2$ monoclinic (insulating) phases of VO$_2$ employing a fully self-consistent combination of density functional theory and embedded dynamical mea
Many strongly correlated transition metal oxides exhibit a metal-insulator transition (MIT), the manipulation of which is essential for their application as active device elements. However, such manipulation is hindered by lack of microscopic underst