@article{10902/35708,
year = {2024},
month = {11},
url = {https://hdl.handle.net/10902/35708},
abstract = {We report the first application of broadband time-resolved pump-probe ellipsometry to study the ultrafast dynamics of the photoinduced insulator-to-metal transition (IMT) in vanadium dioxide (VO₂) thin films driven by 35 fs laser pulses. This novel technique enables the direct measurement of the time-resolved evolution of the complex pseudodielectric function of VO₂ during the IMT. We have identified distinct thermal and nonthermal dynamics in the photoinduced IMT, which critically depends on the pump wavelength and fluence, while providing a detailed temporal and spectral phase map. A comparison of the pseudodielectric function of the VO₂ thin film during thermally and photoinduced phase transitions reveals that the primary differences in the IMT pathways occur within the first picosecond after the pump, driven by nonequilibrium dynamics in this ultrafast time scale. The ultrafast spectroscopic ellipsometry introduced in this work offers a complementary probe to study phase changes in condensed matter and emerging photonic device materials.},
organization = {Y.G. acknowledges the support from the European Union’s Horizon 2020 research and innovation program (No 899598 - PHEMTRONICS) and funding from a Ramon y Cajal Fellowship (RYC2022-037828-I). S.R. acknowledges AFOSR grant FA9550-18-1-0250 for support. S.C. acknowledges funding from the French National Research Agency (ANR) under the project MetaOnDemand (ANR-20-CE24-0013). S.E, S.V.-M., and M.R. acknowledge the project ADONIS (No. CZ.02.1.01/0.0/0.0/16-019/0000789).},
publisher = {American Chemical Society},
publisher = {ACS Photonics, 2024, 11(11), 4883-4893},
title = {Subpicosecond spectroscopic ellipsometry of the photoinduced phase transition in VO₂ thin films},
author = {Gutiérrez Vela, Yael and Vázquez-Miranda, Saúl and Espinoza, Shirly and Khakurel, Krishna and Rebarz, Mateusz and Zhang, Zhen and Saiz Vega, José María and Ramanathan, Shriram and Cueff, Sébastien},
}