Infrared-wave number-dependent metal-insulator transition in vanadium dioxide nanoparticles

Abstract

We have studied the metal-insulator transition (MIT) taking place at 340 K in vanadium dioxide nanoparticles. A peculiar nanosize effect on the 10-nm-sized VO(2) nanoparticles is reported. While the infrared transmittance at high wave numbers displayed a broad transition behavior, the magnetic susceptibility and infrared transmittance at low wave numbers showed a sharp first-order MIT. Our results suggest that the size effect on the MIT is due to the surface region while the core region undergoes the same MIT as that in the bulk. (C) 2010 American Institute of Physics. [doi:10.1063/1.3454783]