DocumentCode :
3016431
Title :
Search for Negative Refraction and Focusing at Optical Wavelengths: Imaging of Quantum Dots Fluorescence in Opal Photonic Crystals
Author :
Rous, Joshua ; Moussa, Rabia ; Aliev, Ali ; Zakhidov, Anvar A.
Author_Institution :
Univ. of Texas at Dallas, Richardson
fYear :
2007
fDate :
6-11 May 2007
Firstpage :
1
Lastpage :
1
Abstract :
Summary form only given. The talk overviews the efforts to achieve negative refraction (NR) in visible and IR by systems, having negative group velocity: photonic crystals (PC) and other systems with strong spatial dispersion of dielectric function, such as gyrotropic crystals and polaritonic media. To search the NR in PCs the fluorescence of CdS and CdSe quantum dots (QD) impregnated into porous silica and polysterene opal photonic crystals have been compared for QDs of different sizes. Spatial distribution of light is visualized by confocal fluorescent microscopy for QDs emitting in blue, green and red spectral bands and compared for PCs matrices having photonic band gaps in different spectral bands. It is found that spatial distribution of fluorescence emission from single QDs and small aggregates of QD is significantly different for QD with fluorescent lines below, within and above PBG frequency in [111]direction. We discuss this different spatial fluorescent patterns in terms of negative refraction in upper photonic bands, which have negative group velocity. The light from QD in the upper band creates patterns, which can be interpreted as due to focusing by the interface between media with positive and negative refraction. We analyze the fluorescence patterns of same size QD in inverted opals, and opals with strong disordering.
Keywords :
II-VI semiconductors; cadmium compounds; fluorescence; light refraction; optical dispersion; optical focusing; optical materials; optical microscopy; photoluminescence; photonic band gap; photonic crystals; porous materials; semiconductor quantum dots; CdS; CdSe; confocal fluorescent microscopy; dielectric function; fluorescence emission; gyrotropic crystals; negative focusing; negative group velocity; negative refraction; optical wavelengths; photonic band gaps; polaritonic media; polysterene opal photonic crystals; porous silica impregnation; quantum dots fluorescence imaging; spatial dispersion; spatial distribution of light; spatial fluorescent patterns; Dielectrics; Fluorescence; Focusing; Gyrotropism; Optical imaging; Optical refraction; Personal communication networks; Photonic crystals; Quantum dots; Silicon compounds;
fLanguage :
English
Publisher :
ieee
Conference_Titel :
Lasers and Electro-Optics, 2007. CLEO 2007. Conference on
Conference_Location :
Baltimore, MD
Print_ISBN :
978-1-55752-834-6
Type :
conf
DOI :
10.1109/CLEO.2007.4453237
Filename :
4453237
Link To Document :
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