Open AccessA role of a picosecond strain in an ultrafast optically-driven phase transition in VO2 nanostructures
Author(s) -
Ia. A. Mogunov,
Sergiy Lysenko,
Anatolii E. Fedianin,
A. J. Kent,
А. В. Акимов,
A. M. Kalashnikova
Publication year - 2020
Publication title -
journal of physics. conference series
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.21
H-Index - 85
eISSN - 1742-6596
pISSN - 1742-6588
DOI - 10.1088/1742-6596/1461/1/012108
Subject(s) - picosecond , femtosecond , materials science , ultrashort pulse , excitation , laser , phase transition , optoelectronics , phase (matter) , optics , molecular physics , condensed matter physics , chemistry , physics , organic chemistry , quantum mechanics
We report on experimental picosecond acoustic studies of an ultrafast photoinduced insulator-to-metal and structural transition in VO 2 nanostructures epitaxially grown on Al 2 O 3 substrates with different orientations. Applying a pump-probe technique with combined excitation of a sample with picosecond strain and femtosecond laser pulses we demonstrate that dynamical strain of moderate amplitude of 0.1% has a pronounced impact on ultrafast photoinduced phase transition in VO 2 nanohillocks. This enables novel path for controlling such transitions at picosecond and nanometer scales. Our experiments also allowed characterizing elastic and photo-elastic properties of the photo-induced metallic phase in VO 2 and to relate them to the properties of the equilibrium phase. Furthermore, we demonstrate the generation of picosecond strain pulses upon laser-induced excitation of thin epitaxial VO 2 .