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Yongfeng Ju Yang Liao Long Zhang Yinglong Sheng Qiang Zhang Danping Chen Ya Cheng Zhizhan Xu Koji Sugioka Katsumi Midorikawa 《Microfluidics and nanofluidics》2011,11(1):111-117
We report on fabrication of large-volume, square-shaped microfluidic chamber embedded in glass by scanning a tightly focused
femtosecond laser beam inside a porous glass immersed in water. After the hollow structure is created in the porous glass
substrate, the fabricated glass sample is post-annealed at 1,050°C during which it can be sintered into a compact glass. By
the use of this technique, a 1 mm × 1 mm × 100 μm microchamber connected to four microfluidic channels is created inside the
transparent glass substrate, showing that our technique allows for fabrication of not only thin channel structures with arbitrary
lengths and configurations, but also hollow structures with infinitely large sizes. 相似文献
3.
《Optical Materials》2005,27(2):241-248
Thin (≈1 μm), waveguiding and c-axis oriented ZnO films of good optical quality have been fabricated on corning glass substrates by r.f. magnetron reactive sputtering without substrate heating. The optical parameters of the films deposited in different O2:Ar sputtering gas mixtures were found to vary. The extraordinary and ordinary refractive indices (ne and no respectively) of the ZnO film grown in 60% O2 and 40% Ar were found to be the highest (ne=1.9876, no=1.9692) and closest to bulk single crystal values, and the birefringence of the film was ≈0.018. The films were annealed at 380 °C in air for 1 h, as a result of which the crystalline quality of the films was found to improve with increase in X-ray density and decrease in stress. While the refractive index decreased, the propagation loss was lowered substantially (3–5 dB/cm) as a result of annealing. The annealed zinc oxide film with minimum stress exhibited lowest loss (3 dB/cm) and highest birefringence (≈0.018). This indicated a correlation between propagation loss and stress. 相似文献
4.
《Optical Materials》2009,31(12):1810-1815
Gd2O3:Eu phosphor powders were prepared by a filter expansion aerosol generator (FEAG) process capable of changing the mean size of droplets. The change in the mean size of the Gd2O3:Eu phosphor powders according to the concentrations of polyethylene glycol added to spray solutions was caused by the difference in the mean size of the droplets produced via the FEAG process. The mean sizes of droplets produced by the FEAG process were affected by the surface tension and viscosity of the spray solutions. The mean sizes of the Gd2O3:Eu phosphor powders obtained from the spray solutions with the same concentration of metal salts changed from 1.5 to 4.2 μm according to the concentrations of polyethylene glycol and citric acid added to the spray solutions. The maximum photoluminescent intensity of the phosphor powders obtained from the spray solutions with polymeric precursors and boric acid flux was 144% of that of the phosphor powders obtained from the aqueous spray solutions without flux. 相似文献
5.
Geng Lin Fangfang Luo Huaihai Pan Qingxi ChenDanping Chen Jianrong Qiu Quanzhong Zhao 《Journal of Alloys and Compounds》2011,509(22):6462-6466
Three individual primary colors were generated from only one piece of Er3+-Eu3+ co-doped oxygen-deficient germanate glass under UV light irradiation. Blue, green, and red emissions were originated from Ge-related oxygen-deficient defect centers (GODCs), Er3+ ions, and Eu3+ ions, respectively. Detailed photoluminescence spectra, decay curve analyses, and electron paramagnetic resonance measurements were carried and the results indicate the existence of energy transfer between Er3+ and Eu3+ ions, GODCs and Eu3+ ions. 相似文献
6.
Botao Wu Jianrong Qiu Mingying Peng Jinjun Ren Xiongwei Jiang 《Materials Research Bulletin》2007,42(4):762-768
We report transparent Ni2+-doped ZnO-Al2O3-SiO2 system glass-ceramics with broadband infrared luminescence. After heat-treatment, ZnAl2O4 crystallite was precipitated in the glasses, and its average size increased with increasing heat-treatment temperature. No infrared emission was detected in the as-prepared glass samples, while broadband infrared luminescence centered at 1310 nm with full width at half maximum (FWHM) of about 300 nm was observed from the glass-ceramics. The peak position of the infrared luminescence showed a blue-shift with increasing heat-treatment temperature, but a red-shift with an increase in NiO concentration. The mechanisms of the observed phenomena were discussed. These glass-ceramics are promising as materials for super broadband optical amplifier and tunable laser. 相似文献
7.
研究了周期量级的圆偏振激光在空气中成丝产生太赫兹辐射的偏振特性。将中心波长1.8 m、脉宽8.6 fs 的圆偏振红外激光脉冲聚焦到空气中,形成等离子体细丝,产生太赫兹辐射。通过测量太赫兹辐射的偏振状态,和偏振方向与驱动激光载波-包络相位的关系,发展太赫兹波偏振控制的方法。实验结果表明,太赫兹辐射为椭圆偏振,而且偏振平面随着驱动激光载波-包络相位的变化而转动。这对太赫兹波的偏振控制有重要意义,并为周期量级激光载波-包络相位的测量提供了新方法。 相似文献
8.
光学元器件的激光损伤问题,一直以来都困扰着超强超短激光系统的进一步发展。飞秒激光领域,激光脉冲引起的光学器件损伤主要由材料的本征特性决定。光学材料内的多光子电离、雪崩电离、导带电子弛豫等一系列非线性过程,与材料的激光损伤过程密切相关。利用泵浦探测技术,采用中心波长为800 nm,重复频率1 kHz的飞秒激光脉冲,对Nb2O5/SiO2啁啾镜介质膜的内部与飞秒激光损伤相关的超快动力学进行了研究。发现强的泵浦光脉冲辐照结束后飞秒乃至几十皮秒的范围内,啁啾镜对探测光的反射率有一定程度的下降。反射率降低的主要原因是泵浦光在介质膜的Nb2O5层内激发的大量的自由电子对探测光吸收所致,且该过程对激光诱导损伤过程起主导作用。通过反射率的变化,对其介质膜内导带电子弛豫过程进行探究,测定得到其衰减寿命,分别为1.31、6.88、22.34 ps。 相似文献
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利用紫外飞秒激光光谱技术研究了Al2O3/SiO2高反射膜内的超快载流子动力学。通过实验,发现该反射膜Al2O3层的载流子动力学在紫外反射膜的激光诱导损伤中起着至关重要的作用。通过泵浦-探测实验,发现紫外飞秒激光与光学薄膜作用后,光学薄膜反射率有所下降,且探测光反射率变化的峰值在约2.3 ps的时间内从417 nm左右转移到402 nm左右。为了更好的解释激光诱导载流子动力学,一个具体的理论模型被提出来,该模型指出导带自由电子弛豫过程中与晶格相互作用,产生距导带一个光子能量的中间缺陷态,其初始电子密度影响了材料损伤阈值高低。通过该理论模型得出的激光损伤阈值数据和实验数据吻合得很好。 相似文献