Phase transition-governed opal-VO2 photonic crystal

Three-dimensional opal-VO2 photonic crystals were prepared by the chemical bath deposition technique. The x-ray diffraction and Raman spectroscopic da ta confirm the crystalline perfection of VO2 impregnated into synthetic opa l pores. It is shown from the optical reflectivity measurements that the ph otonic bandgap of the opal-VO2 composite is governed by the phase transitio n in VO2. (C) 2001 American Institute of Physics.