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Vanadium dioxide VO2 belongs to a class of materials including ferroelectrics, which hold great promise for future high-speed optical switches and other opto-electronic devices. In such materials, it is established that there is a strong relationship between structural and electronic effects, yet a much better understanding of the fundamental physics behind these effects is needed before they can be technologically exploited at the commercial level. Being a smart oxide, transiting at a temperature of Tc~340.8K, stoichiometric VO2 undergoes an exclusive and a unique 1st order metal-insulator electronic transition, which is accompanied by a sharp structural crystallographic transition from a low-temperature monoclinic phase to a high-temperature rutile phase. The latter result causes a sharp change in the resistivity over several orders of magnitude induced by the band gap closing. From photonics point of view, this reversible metal-insulator electronic transition is accompanied by a significant and reversible variation of the refractive index under an external stimulus such as temperature. Hence, VO2 based coatings have been attracting considerable interest both from fundamental & technological grounds. The sound technological potentialities include applications such as (i) smart windows for solar heat modulation, (ii) active coating for heat management in satellites, (iii) ultralight compact bolometry, (iv) ultrafast optical limiting and (v) femtosecond tunable nanoplasmonics. While it took a half-century since the pioneering works of Morin and Sir Neville Mott to measure the duration of the singular 1st order metal-insulator electronic transition of VO2 which was found to be in the femtosecond regime by Cavalleri et al , this Swiss-South African research proposal is aiming to map for the first time the thermal variation of the carriers’ density and its dynamic in nano-scaled VO2 1-D type nanorods by Terahertz spectroscopy as well as to demonstrate the feasibility of a femtosecond photo-induced optoelectronic nano-gating. The established and complementary track records of the South African and Swiss teams in the fields of VO2 nanoscaled material and Terahertz spectroscopy respectively would guarantee the full finalization of this joint project in view of technological applications in opto-electronic femtosecond single nano-gating. In parallel to the targeted scientific and technological objectives which are at the forefront of the current science status, and in view of the human capital development aspect, an identified cohort of postgraduate fellows will be trained and mentored by both PIs in the field of VO2 smart coatings physics and Terahertz spectroscopy respectively.