Second-harmonic generation in Ge20As25S55 glass irradiated by an electron beam

Second-harmonic generation was observed in Ge(20)AS(25)S(55) chalcogenide glass irradiated by an electron beam. The second-harmonic intensity increased with increasing electron-beam current and accelerating voltage. The second-harmonic generation in Ge20As25S55 glass was caused by the space-charge electrostatic field that was generated by irradiation of an electron beam. Second-order nonlinearity chi ((2)) as great as 0.8 pm/V was obtained. The results of measurements of thermally stimulated depolarization current indicated that the glass was poled in the thin layers of its surface (several micrometers) and that the nonlinearity was stable. (C) 2001 Optical Society of America.

PIXE and ICP-AES analysis of early glass unearthed from Xinjiang (China)

Early glasses (about 1066 BC-220 AD) unearthed from Xinjiang of China were chemically characterized by using PIXE and ICP-AES. It was found that these glasses were basically attributed to PbO-BaO-SiO2 system, K2O-SiO2 system, Na2O-CaO-SiO2 system and Na2O-CaO-PbO-SiO2 system. The results from the cluster analysis showed that some glasses had basically similar recipe and technology. The PbO-BaO-SiO2 glass and the K2O-SiO2 glass were thought to come from the central area and the south of ancient China, respectively. The part of the Na2O-CaO-SiO2 glass (including the Na2O-CaO-PbO-SiO2 glass) might be imported from Mesopotamia, while the other part might be locally produced. (c) 2005 Elsevier B.V. All rights reserved.