Article

Photoinduced phase transition in VO2 nanocrystals: ultrafast control of surface-plasmon resonance

Department of Physics and Astronomy, Vanderbilt University, Нашвилл, Michigan, United States
Optics Letters (Impact Factor: 3.18). 04/2005; 30(5):558-60. DOI: 10.1364/OL.30.000558
Source: PubMed

ABSTRACT We study the ultrafast insulator-to-metal transition in nanoparticles of VO2, obtained by ion implantation and self-assembly in silica. The nonmagnetic, strongly correlated compound VO2 undergoes a reversible phase transition, which can be photoinduced on an ultrafast time scale. In the nanoparticles, prompt formation of the metallic state results in the appearance of surface-plasmon resonance. We achieve large, ultrafast enhancement of optical absorption in the near-infrared spectral region that encompasses the wavelength range for optical-fiber communications. One can further tailor the response of the nanoparticles by controlling their shape.

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