We have prepared a silica colloidal crystal with ethanol, which has a face-centered cubic structure and a corresponding photonic band gap located in the visible region, determined by Kossel ring analysis and the trans...We have prepared a silica colloidal crystal with ethanol, which has a face-centered cubic structure and a corresponding photonic band gap located in the visible region, determined by Kossel ring analysis and the transmission spectra. A special feature is an apparent variation of its lattice constant, as well as the gap frequency, with sample height. The Raman scattering induced by a picosecond laser at different heights of the colloidal crystal has been measured. It is found that the intensity of the Raman scattering is not related sensitively to the photonic gap, even though the Raman-Stokes wavelength is inside the gap.展开更多
A novel two-dimensional photonic crystal that possesses absolute photonic band gaps for both transverse-magnetic and transverse-electric polarized waves is proposed.Plane wave method is used for calculating their phot...A novel two-dimensional photonic crystal that possesses absolute photonic band gaps for both transverse-magnetic and transverse-electric polarized waves is proposed.Plane wave method is used for calculating their photonic band structures.Results show that,for this structure,two absolute photonic band gaps appear in dielectric cylinders periodically imbedded in an air background.展开更多
基金Supported by the National Natural Science Foundation of China under Grant No.19774073.
文摘We have prepared a silica colloidal crystal with ethanol, which has a face-centered cubic structure and a corresponding photonic band gap located in the visible region, determined by Kossel ring analysis and the transmission spectra. A special feature is an apparent variation of its lattice constant, as well as the gap frequency, with sample height. The Raman scattering induced by a picosecond laser at different heights of the colloidal crystal has been measured. It is found that the intensity of the Raman scattering is not related sensitively to the photonic gap, even though the Raman-Stokes wavelength is inside the gap.
基金Supported by the National Natural Science Foundation of China under Grant No.19574069.
文摘A novel two-dimensional photonic crystal that possesses absolute photonic band gaps for both transverse-magnetic and transverse-electric polarized waves is proposed.Plane wave method is used for calculating their photonic band structures.Results show that,for this structure,two absolute photonic band gaps appear in dielectric cylinders periodically imbedded in an air background.
