The origin and properties of second-harmonic generation (SHG) from crystalline particles and their crystalline phases in GeO2-SiO 2 glass films were investigated. GeO2-SiO2 glass films with a thickness of approximately 5 μm were fabricated by the chemical vapor-phase deposition (CVD) method. Heat treatments in the temperature range of 1100-1260°C for durations of 2-8 h have been performed to crystallize the glass films. X-ray diffraction (XRD) peaks at around 2θ = 22° in the crystallized GeO2-SiO2 films were observed, and the obtained XRD patterns in the glass films are exactly the same as those in ultraviolet (UV) poled GeO2-SiO2 glasses with a large second-order optical nonlinearity comparable to that in LiNbO 3 crystals. Using a SHG microscopic technique, it has been found that the intensity of SHG emission from crystalline particles is clearly dependent on stress-induced optical retardation which is accompanied by the formation of crystalline particles of the pseudo-β-cristobalite containing GeO2. In addition, a new technique for enhancing the intrinsic SHG by means of modification of defect states is demonstrated.
|ジャーナル||Japanese Journal of Applied Physics, Part 1: Regular Papers and Short Notes and Review Papers|
|出版ステータス||Published - 2003 12|
ASJC Scopus subject areas
- Physics and Astronomy(all)