Author Affiliations
Abstract
1 MOE Key Laboratory of Advanced Micro-Structured Materials, School of Physics Science and Engineering, Tongji University, Shanghai 200092, China
2 Institute of Precision Optical Engineering, School of Physics Science and Engineering, Tongji University, Shanghai 200092, China
3 School of Aerospace Engineering and Applied Mechanics, Tongji University, Shanghai 200092, China
Rotating elliptical nanowire arrays as two-dimensional photonic crystals has been proposed and studied in this Letter. The analysis of the four lowest energy bands and the first bandgap width of some examples illustrates that the rotation and configuration of the primitive cell can have effects on the reducibility of the Brillouin zone. As the central element’s orientation changes, the irreducible Brillouin zone could be expanded to the whole first Brillouin zone. Special attention has been paid to the nanowire arrays with adjacent elements perpendicular to each other, and the irreducible Brillouin zone unexpectedly retracted back to the 1/8 of the first Brillouin zone though the symmetry of elements is lower than that of the square lattice. Meanwhile, the first bandgap width of the perpendicular array can be adjusted by the rotation of each primitive element.
Brillouin zone bandgap symmetry perpendicular elliptical nanowires rotation Chinese Optics Letters
2020, 18(6): 063601
提出了一种基于结构光投影在线测量大尺度物体的方法, 并给出了理论论证, 通过模拟测量发现, 分割子图像部分包含的变形条纹不是条纹周期的整数倍, 相位展开时不可避免出现错误, 造成拼接处误差比较大, 因此提出利用拼接处相邻相位展开正确的数据对拼接处的数据进行插值处理, 有效减小了误差, 验证了方法的可行性; 解决了动态大尺度物体三维面型测量受单个投影设备投影范围限制的问题, 在实际工程应用中, 精度要求不高的情况下, 可以用来对动态的大尺度物体进行三维建模。
在线测量 大尺度物体 傅里叶变换轮廓术 双频正弦光栅 online measurement large scale object Fourier transform profilometry double frequency sinusoidal grating
Author Affiliations
Abstract
Dual-grating structure thin-film silicon solar cells with different front and back grating periodicities are designed The geometrical parameters of both gratings are investigated. The reflection is greatly reduced by the front grating, whereas the absorption in the long wavelength is increased because of the back grating. The short circuit current of the combined structure is enhanced by 16.8% for a 1-\mu m thick c-Si layer compared with that of the conformal grating structure. The short circuit current can be further increased by creating a relative lateral displacement between the front and back gratings. The displacement results in a more remarkably enhanced absorption when the thickness of the active layer is reduced, indicating its importance in the design of ultra-thin high-efficiency solar cells.
050.2770 Gratings 350.2770 Gratings 350.6050 Solar energy Chinese Optics Letters
2013, 11(12): 120501
Author Affiliations
Abstract
Light scattering properties of back grating structures that composed of one-dimensional ZnO gratings and a flat 300-nm Al reflectors are investigated. Results show that grating structures cause an 8% reduction of the total reflectivity, as grating periods increasing from 620 to 1 435 nm, both the diffuse reflectivity and the haze parameter enhance drastically between 400 and 1 000 nm, whereas the diffraction angle at normal incidence reduce greatly, which agree with the values calculated from grating equation. It is concluded that rear gratings have the potential of scattering a substantial amount of incident light to specific angles and enlarging the optical path.
050.1950 Diffraction gratings 310.6188 Spectral properties 220.4000 Microstructure fabrication Chinese Optics Letters
2013, 11(s1): S10504
Author Affiliations
Abstract
In this letter, a design with both metal nanoparticles and back diffraction gratings is put forward for enhancing the efficiency of thin film silicon solar cells. The coupling mechanism between the metal nanoparticles and silicon absorber layer, and that between the incident light and the modes of the silicon absorption layer through the grating layer are both analyzed. The interaction between the front metal nanoparticles and back gratings is analyzed, which substantially increases the light trapping by 58% compared to flat solar cell.
350.6050 Solar energy 050.1950 Diffraction gratings 250.5403 Plasmonics Chinese Optics Letters
2013, 11(s1): S10503
同济大学 精密光学工程技术研究所, 上海 200092
以激光干涉法得到的光刻胶图案为掩模, 采用湿法刻蚀和溶脱-剥离法制备了具有良好减反射特性的亚微米掺铝氧化锌(ZnO:Al, AZO)光栅。表面形貌特征和反射光谱测试结果表明, 湿法刻蚀较溶脱-剥离法得到的AZO光栅表面更为粗糙, 两者均方根粗糙度分别为25.4, 7.6 nm。在400～900 nm波段, 两种方法制备的周期和高度相同的光栅, 平均总反射率分别由AZO薄膜的12.5%下降到8.3%和10.2%。两者的平均镜面反射率分别为6.2%和6.6%, 平均漫反射率分别为2.1%和3.6%。湿法刻蚀得到的表面较为粗糙AZO光栅的漫反射明显减弱, 从而导致总的减反特性优于溶脱-剥离法得到的表面起伏相对较小的AZO光栅。
亚微米光栅 掺铝氧化锌 激光干涉法 湿法刻蚀 溶脱-剥离法 submicron gratings aluminum-doped zinc oxide laser interference lithography wet etching lift-off technology 强激光与粒子束
2012, 24(11): 2613
同济大学精密光学工程技术研究所, 上海 200092
探讨亚微米掺铝氧化锌（AZO）光栅的漫透射光谱特性。在AZO薄膜上涂布光刻胶，用325 nm激光双光束干涉曝光得到掩模图案。将其置于质量分数为0.5%的稀盐酸溶液中湿法刻蚀，制备出周期(780~1280 nm)和高度（60~300 nm）能独立调控的AZO一维光栅。正入射双向透射分布函数（BTDF）测试结果表明，400~900 nm波段内平均镜面透射率随光栅周期增大而降低，与紫外可见分光光度计测得的结果吻合；同时，周期越大被衍射到30°~80°范围内的漫透射比重和漫透射峰值均越大，而峰位角越小。根据光栅方程对实验结果给出了合理的解释。
光栅 掺铝氧化锌 双向透射分布函数 激光干涉法 湿法刻蚀
1 同济大学物理系, 上海 200092
2 黄山学院信息工程学院, 安徽 黄山245021
3 华东师范大学物理系, 上海200062
目的: 探讨弱磁场对提取的骨骼肌肌质网系(SR)Ca2+转运、钙泵(Ca2+-Mg2+-ATPase) 及钙释放通道(RyR)活性的影响, 从分子水平和细胞信号系统的角度来解释生物电磁效应。 方法: 利用动态光谱法检测0.4 mT弱磁场辐照过的SR Ca2+转运、Ca2+-ATPase活性, 还原型辅酶(NADH)的氧化初速率和超氧(O2-·)产率, 以及用同位素标记方法检测［3H］-Ryanodine与RyR的平衡结合度。结果: 弱磁场辐照引起SR的Ca2+摄取功能和Ca2+-ATPase的活性明显下降, Ca2+释放和［3H］-Ryanodine平衡结合度上升, 同时上调了 NADH的氧化初速率和O2-·的产率。 结论: 提示0.4 mT弱磁场辐照30 min对SR Ca2+-ATPase活性有明显抑制, 对RyR有一定的激活效果。
弱磁场 肌质网 钙调控 钙泵 钙释放通道 weak magnetic field sarcoplasmic reticulum calcium modulation Ca2+-ATPase ryanodine receptor
Author Affiliations
Abstract
Institute of Precision Optical Engineering, Tongji University, Shanghai 200092, China
A bandpass filter with twin wideband channels in a single-layer guided-mode resonance grating is presented. Strong refractive-index modulation is used to support the excitation of multimode resonances TE1,0, TE1,1, TE2,0, TE1,2, and TE2,1, which are excited by the first and second diffraction orders, relate asymmetrical line shapes and broad low-transmission bands, where TE is the transverse electric. Taking advantage of narrow linewidth and sharp edge line shape in the spectra of TE2, (v is the mode), a bandpass filter with form factors of 0.61 and 0.7 for long- and short-wave channels is presented to demonstrate this concept.
导模共振 光栅 模式 带通滤光片 矩形度 050.1950 Diffraction gratings 310.2790 Guided waves 310.6860 Thin films, optical properties Chinese Optics Letters
2011, 9(8): 080501
采用直流磁控溅射法制备自支撑锆(Zr)膜,采用二步法制备聚酰亚胺(PI)膜, 在Zr膜表面沉积PI膜得到自支撑PI/Zr复合膜。均苯四甲酸酐(PMDA)和二甲基二苯醚(ODA)在二甲基乙酰胺(DMAC)中反应得到聚酰胺酸(PAA), 然后PAA高温亚胺化得到PI;PI成膜时采用提拉法成膜。经国家同步辐射实验室计量线站测定, 实际测量结果与理论分析一致, PI膜的引入虽然会导致自支撑薄膜透过率有所下降, 但在类镍-银软X射线13.9 nm波段PI(200 nm)/Zr(300 nm)和PI(200 nm)/Zr(400 nm)自支撑薄膜的透过率仍然分别达到14.9%和7.5%。
自支撑薄膜 聚酰亚胺 聚酰胺酸 二步法 亚胺化 质量吸收系数 free-standing film polyimide polyamic acid two-step process imidization mass absorption coefficient
