ABSTRACTFemtosecond laser irradiation has various noticeable effects on fused silica. It can loca... more ABSTRACTFemtosecond laser irradiation has various noticeable effects on fused silica. It can locally increase the index of refraction or modify the material chemical selectivity. Regions that have been exposed to the laser are etched several times faster than unexposed regions. Various observations reported in the literature seem to show that these effects are possibly related to a combination of structural changes and the presence of internal stress. However, a detailed analysis of the contribution of both effects is still lacking.In this paper, we present systematic SEM-based investigations performed on fused silica (a-SiO2). Line-patterns were first scanned on the substrate using a femtosecond laser and then etched in a low-concentration HF solution. The effects of various laser parameters like power and scanning speed are analyzed and we show further evidence of an interface between two different etching regimes.
Electro-Optical Materials for Switches, Coatings, Sensor Optics, and Detectors, 1990
ABSTRACT Nonlinear refractive index and two-photon absorption measurements on semiconductors show... more ABSTRACT Nonlinear refractive index and two-photon absorption measurements on semiconductors show that the bound electronic nonlinearity can be calculated from two-photon absorption dispersion via a simple Kramers- Kronig analysis. This analysis shows n2 changing from positive to negative as the photon energy approaches the band-gap energy, consistent with observations. Additionally, this simple calculation, which assumes two parabolic bands, gives good agreement with measured values of n2 in wide-gap dielectrics that are 2 to 3 orders of magnitude smaller than in semiconductors.
Purpose – Enterprise resource planning (ERP) systems if successfully implemented bring about comp... more Purpose – Enterprise resource planning (ERP) systems if successfully implemented bring about competitive advantages. On the other hand, project failure could, in an extreme case, cause an organisation to go out of business. Mapped against existing literature on ERP critical success factors, this paper examines environmental factors that impacted on the adoption of ERP by The Oman Telecommunication Company (Omantel).
ABSTRACTFemtosecond laser irradiation has various noticeable effects on fused silica. It can loca... more ABSTRACTFemtosecond laser irradiation has various noticeable effects on fused silica. It can locally increase the index of refraction or modify the material chemical selectivity. Regions that have been exposed to the laser are etched several times faster than unexposed regions. Various observations reported in the literature seem to show that these effects are possibly related to a combination of structural changes and the presence of internal stress. However, a detailed analysis of the contribution of both effects is still lacking.In this paper, we present systematic SEM-based investigations performed on fused silica (a-SiO2). Line-patterns were first scanned on the substrate using a femtosecond laser and then etched in a low-concentration HF solution. The effects of various laser parameters like power and scanning speed are analyzed and we show further evidence of an interface between two different etching regimes.
Electro-Optical Materials for Switches, Coatings, Sensor Optics, and Detectors, 1990
ABSTRACT Nonlinear refractive index and two-photon absorption measurements on semiconductors show... more ABSTRACT Nonlinear refractive index and two-photon absorption measurements on semiconductors show that the bound electronic nonlinearity can be calculated from two-photon absorption dispersion via a simple Kramers- Kronig analysis. This analysis shows n2 changing from positive to negative as the photon energy approaches the band-gap energy, consistent with observations. Additionally, this simple calculation, which assumes two parabolic bands, gives good agreement with measured values of n2 in wide-gap dielectrics that are 2 to 3 orders of magnitude smaller than in semiconductors.
Purpose – Enterprise resource planning (ERP) systems if successfully implemented bring about comp... more Purpose – Enterprise resource planning (ERP) systems if successfully implemented bring about competitive advantages. On the other hand, project failure could, in an extreme case, cause an organisation to go out of business. Mapped against existing literature on ERP critical success factors, this paper examines environmental factors that impacted on the adoption of ERP by The Oman Telecommunication Company (Omantel).
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