LiAlO2 single crvstals doped with Ti at concentration 0.2at.% are grown by the Czochralskl technique with dimensions φ42×55mm. Ti ions in the crystal are quadrivalence proven by comparing the absorption and fluo...LiAlO2 single crvstals doped with Ti at concentration 0.2at.% are grown by the Czochralskl technique with dimensions φ42×55mm. Ti ions in the crystal are quadrivalence proven by comparing the absorption and fluorescence spectra of pure LiAlO2 and Ti： LiAlO2. After air and Li-rich atmosphere annealing, the absorption peaks in the range of 600-800nm disappear. We conclude that 682 and 756nm absorption peaks are attributed to the VLi and Vo absorptions, respectively： The peaks at 716nm and 798nm may stem from the VLi^＋ and absorptions. The colour-centre model can be applied to explain the experimental phenomena. Ti^4＋-doping produces more lithium vacancies in the LiAlO2 crystal. The intensities of [LiO4] and the associated bonds remain unchanged, which improves the anti-hydrolyzation and thermal stability of LiAlO2 crystals.展开更多
研究了利用化学气相沉积法在镓酸锂(001)基板上生长氧化锌薄膜,探讨了生长温度、生长压力、生长时间对薄膜结构与特性的影响,以期寻找出生长高品质氧化锌(0002)薄膜的最佳条件。研究结果表明,在氧气与氮气流量比为600/400、生长压力为6....研究了利用化学气相沉积法在镓酸锂(001)基板上生长氧化锌薄膜,探讨了生长温度、生长压力、生长时间对薄膜结构与特性的影响,以期寻找出生长高品质氧化锌(0002)薄膜的最佳条件。研究结果表明,在氧气与氮气流量比为600/400、生长压力为6.67 k Pa、生长温度为550℃、生长时间为60 min条件下,于镓酸锂(001)基板上能够生长出高质量的氧化锌(0002)薄膜。展开更多
This paper reports that polarized far-infrared reflectivity measurements have been done on LiGaO2 single crystal along two crystalline taxes at different temperatures. The temperature dependent frequencies of the long...This paper reports that polarized far-infrared reflectivity measurements have been done on LiGaO2 single crystal along two crystalline taxes at different temperatures. The temperature dependent frequencies of the longitudinal and transverse optical phonon have been obtained from the real part of optical conductivity and the loss function respectively. A small Drude component is observed at frequency below 300 cm^-1 which could arise from Li ions or oxygen deficiencies. The ionicity of LiGaO2 has been studied from the analysis of the Born effective charge of different ions.展开更多
文摘LiAlO2 single crvstals doped with Ti at concentration 0.2at.% are grown by the Czochralskl technique with dimensions φ42×55mm. Ti ions in the crystal are quadrivalence proven by comparing the absorption and fluorescence spectra of pure LiAlO2 and Ti： LiAlO2. After air and Li-rich atmosphere annealing, the absorption peaks in the range of 600-800nm disappear. We conclude that 682 and 756nm absorption peaks are attributed to the VLi and Vo absorptions, respectively： The peaks at 716nm and 798nm may stem from the VLi^＋ and absorptions. The colour-centre model can be applied to explain the experimental phenomena. Ti^4＋-doping produces more lithium vacancies in the LiAlO2 crystal. The intensities of [LiO4] and the associated bonds remain unchanged, which improves the anti-hydrolyzation and thermal stability of LiAlO2 crystals.
文摘研究了利用化学气相沉积法在镓酸锂(001)基板上生长氧化锌薄膜,探讨了生长温度、生长压力、生长时间对薄膜结构与特性的影响,以期寻找出生长高品质氧化锌(0002)薄膜的最佳条件。研究结果表明,在氧气与氮气流量比为600/400、生长压力为6.67 k Pa、生长温度为550℃、生长时间为60 min条件下,于镓酸锂(001)基板上能够生长出高质量的氧化锌(0002)薄膜。
基金supported by the National Natural Science Foundation of China (Grant No 10474128)
文摘This paper reports that polarized far-infrared reflectivity measurements have been done on LiGaO2 single crystal along two crystalline taxes at different temperatures. The temperature dependent frequencies of the longitudinal and transverse optical phonon have been obtained from the real part of optical conductivity and the loss function respectively. A small Drude component is observed at frequency below 300 cm^-1 which could arise from Li ions or oxygen deficiencies. The ionicity of LiGaO2 has been studied from the analysis of the Born effective charge of different ions.
