Roman scattering measurement of （ 1 - x ） GeS2-x Ga2S3 system glasses was conducted in order to understand the microstructural change caused by the addition of Ga2S3 . According to the change of Raman spectra with t...Roman scattering measurement of （ 1 - x ） GeS2-x Ga2S3 system glasses was conducted in order to understand the microstructural change caused by the addition of Ga2S3 . According to the change of Raman spectra with the addition of Ga2S3, two main structural transformations were deduced ： the gradual enhancement of ethane- like structural units S3 Ge- GeS3 （ 250 cm ^- 1） and S3 Ga- GaS3 （270 cm ^- 1 ） and the appearance of charge imbalanced units [ Ga2 S2 （ S1/2 ）4 ]^2- and [Ga（ S1/2 ）4 ]^- . And this change of structural aspect seems to give as a clue to understanding the cause of the increased rare-earth solubility.展开更多
With the pulsed laser deposition （PLD） method, amorphous 80GeS2-15Ga2S3-5CdS chalcogenide film was deposited on glassy substrate. Obvious second harmonic generation （SHG） was observed in the ultraviolet （UV）-pol...With the pulsed laser deposition （PLD） method, amorphous 80GeS2-15Ga2S3-5CdS chalcogenide film was deposited on glassy substrate. Obvious second harmonic generation （SHG） was observed in the ultraviolet （UV）-polarized film and the SHG intensity increased with the increase in single pulse energy and irradiation time. Through Raman spectra and transmission spectra, the mechanism of SHG was studied. The experimental results demonstrated that effective electron traps and hole traps were generated in the UV- polarized film. The energy of electrons and holes was using up due to the collision with other particles and crystal fields during their movement and finally they were captured by the traps and fixed, which made the electric charge distribution nonuniform in the film and destroyed the spatial isotropy. In the meantime, the center of positive and negative charges separated and a built-in electric field was formed which generated the optical second-order nonlinearity of the film.展开更多
文摘Roman scattering measurement of （ 1 - x ） GeS2-x Ga2S3 system glasses was conducted in order to understand the microstructural change caused by the addition of Ga2S3 . According to the change of Raman spectra with the addition of Ga2S3, two main structural transformations were deduced ： the gradual enhancement of ethane- like structural units S3 Ge- GeS3 （ 250 cm ^- 1） and S3 Ga- GaS3 （270 cm ^- 1 ） and the appearance of charge imbalanced units [ Ga2 S2 （ S1/2 ）4 ]^2- and [Ga（ S1/2 ）4 ]^- . And this change of structural aspect seems to give as a clue to understanding the cause of the increased rare-earth solubility.
基金Funded by the National Natural Science Foundaition of China(Nos.51172169 and 61177084),NCET\(NCET-11-0687)the Fundamental Research Funds for the Central Universities(Wuhan University of Technology)
文摘With the pulsed laser deposition （PLD） method, amorphous 80GeS2-15Ga2S3-5CdS chalcogenide film was deposited on glassy substrate. Obvious second harmonic generation （SHG） was observed in the ultraviolet （UV）-polarized film and the SHG intensity increased with the increase in single pulse energy and irradiation time. Through Raman spectra and transmission spectra, the mechanism of SHG was studied. The experimental results demonstrated that effective electron traps and hole traps were generated in the UV- polarized film. The energy of electrons and holes was using up due to the collision with other particles and crystal fields during their movement and finally they were captured by the traps and fixed, which made the electric charge distribution nonuniform in the film and destroyed the spatial isotropy. In the meantime, the center of positive and negative charges separated and a built-in electric field was formed which generated the optical second-order nonlinearity of the film.
