If you are looking for high-quality products, please feel free to contact us and send an inquiry, email: brad@ihpa.net
vanadium iv oxide is a fascinating and unique strongly correlated material that has received renewed interest with the development of ultrafast imaging techniques, microscopy techniques, ionic gating, and improved computational approaches. The reversible phase transition of VO2 from its insulator to metallic monoclinic phase (MIT-CPT) is characterized by dramatic changes in the optical and electrical properties of the material.
It is also a material with an unusual property: it can be induced to exhibit a phase transition by various external stimuli such as temperature, pressure, electric and magnetic fields, carrier injection or photo-excitation1,2,3,4. In these situations the atomic structure of the material changes in a way that can be difficult to explain using purely geometrical considerations. In particular, the atomic dimerization of V atoms (V-V) leads to the formation of distinct metastable monoclinic metal phases that are not readily explained by classical lattice-electron interactions5.
In these phase-change materials, the metal-insulator transition is accompanied by strong non-linear optical and electrical responses, leading to a wide range of applications in opto-electronics and optical modulation, including passive smart solar energy harvesting, stationary optical shutters, and the irradiation-based self-cleaning of windows. Until recently, the physics behind these effects was unclear and largely unresolved.
The underlying physics is a complex interplay between the energy levels of the different orbitals in the metal-insulator transition region. This interaction can be described by a series of mechanisms including the depopulation of the V-V bonding orbitals, the creation of an empty band gap and the stabilization of a non-electronic, monoclinic metallic state.