反应气体中添加体积分数0.001%的N2,研究CVD金刚石PL(photoluminescence spectroscopy,PL)光谱发现,与N杂质相关的[NV]0与[NV]-和与Si杂质相关的[SiV]是金刚石中的主要杂质缺陷。经过高温高压(high temperature and high pressure,HPHT...反应气体中添加体积分数0.001%的N2,研究CVD金刚石PL(photoluminescence spectroscopy,PL)光谱发现,与N杂质相关的[NV]0与[NV]-和与Si杂质相关的[SiV]是金刚石中的主要杂质缺陷。经过高温高压(high temperature and high pressure,HPHT)处理后,[NV]0峰的强度被削弱,[NV]-峰的强度被增强,[SiV]峰的强度被显著增强,并新出现了[SiV]-宽峰。反应气体中N2体积分数降至0.0001%并添加0.5%的O2后,[NV]0与[NV]-峰消失,O2升高至1%后[SiV]峰强度出现了明显降低,继续升高O2含量,[SiV]峰强度下降趋势变缓,这些现象证明了添加少量O2有助于CVD金刚石中N和Si杂质缺陷的抑制与消除。展开更多
Pure and F,GeO2-doped silica glass cut from fiber preforms prepared by plasma assisted chemical vapor deposition(PCVD) were investigated by ultraviolet absorption spectroscopy.The ultraviolet absorption characterist...Pure and F,GeO2-doped silica glass cut from fiber preforms prepared by plasma assisted chemical vapor deposition(PCVD) were investigated by ultraviolet absorption spectroscopy.The ultraviolet absorption characteristics of these glasses were also studied after UV laser irradiation and heating treatment.It was found that absorption band near 240 nm assigned to GODC was found both in GeO2-doped and F-GeO2 co-doped silica glass,but absorption intensity of the latter was lower than that of the former.It's because F can react with GODC and GeE′ simultaneously and reduce their concentration.After irradiation,UV absorption change of F-GeO2 co-doped silica glass was weaker than that of GeO2-doped silica glass,it thus can be concluded that introduction of F could depress the UV absorption of GeO2-doped silica core effectively.展开更多
In the present research, mixed crystals KCl1–xBrx (x = 0.1, 0.3, 0.5, 0.7 & 0.9) were grown by Czochralski method. Then some analysis such as chemical etching, XRD, and absorbing spectrum were established on the ...In the present research, mixed crystals KCl1–xBrx (x = 0.1, 0.3, 0.5, 0.7 & 0.9) were grown by Czochralski method. Then some analysis such as chemical etching, XRD, and absorbing spectrum were established on the irradiated crystals by γ-ray. The results of this research show that configuration of defects in mixed crystals in contrast with pure crystals is different. Somehow that type and percentage of cumulative composition cause to changing in lattice parameter and lattice defect density in alkali halide crystals and finally change optical properties of crystal.展开更多
文摘反应气体中添加体积分数0.001%的N2,研究CVD金刚石PL(photoluminescence spectroscopy,PL)光谱发现,与N杂质相关的[NV]0与[NV]-和与Si杂质相关的[SiV]是金刚石中的主要杂质缺陷。经过高温高压(high temperature and high pressure,HPHT)处理后,[NV]0峰的强度被削弱,[NV]-峰的强度被增强,[SiV]峰的强度被显著增强,并新出现了[SiV]-宽峰。反应气体中N2体积分数降至0.0001%并添加0.5%的O2后,[NV]0与[NV]-峰消失,O2升高至1%后[SiV]峰强度出现了明显降低,继续升高O2含量,[SiV]峰强度下降趋势变缓,这些现象证明了添加少量O2有助于CVD金刚石中N和Si杂质缺陷的抑制与消除。
文摘Pure and F,GeO2-doped silica glass cut from fiber preforms prepared by plasma assisted chemical vapor deposition(PCVD) were investigated by ultraviolet absorption spectroscopy.The ultraviolet absorption characteristics of these glasses were also studied after UV laser irradiation and heating treatment.It was found that absorption band near 240 nm assigned to GODC was found both in GeO2-doped and F-GeO2 co-doped silica glass,but absorption intensity of the latter was lower than that of the former.It's because F can react with GODC and GeE′ simultaneously and reduce their concentration.After irradiation,UV absorption change of F-GeO2 co-doped silica glass was weaker than that of GeO2-doped silica glass,it thus can be concluded that introduction of F could depress the UV absorption of GeO2-doped silica core effectively.
文摘In the present research, mixed crystals KCl1–xBrx (x = 0.1, 0.3, 0.5, 0.7 & 0.9) were grown by Czochralski method. Then some analysis such as chemical etching, XRD, and absorbing spectrum were established on the irradiated crystals by γ-ray. The results of this research show that configuration of defects in mixed crystals in contrast with pure crystals is different. Somehow that type and percentage of cumulative composition cause to changing in lattice parameter and lattice defect density in alkali halide crystals and finally change optical properties of crystal.