沈阳航空航天大学 自动化学院，辽宁 沈阳 110036
振动能量在自然界中广泛存在，利用智能材料收集振动能量为微电子系统供电是新能源领域的发展趋势。该文利用新型智能材料磁控形状记忆合金(MSMA)的逆效应研究设计了一种基于悬臂梁式的MSMA振动能量采集器，对采集器的各部分结构进行理论分析和系统设计，并建立了振动能量采集器的结构模型。利用ANSYS软件对磁场进行有限元分析，验证了磁场回路和磁感应强度满足采集振动能量的要求。在此基础上，研制了采集器样机，并通过搭建实验平台对采集器进行实验测试，结果表明，该悬臂梁式MSMA振动能量采集器具有较宽的振动能量采集频带，输出电压可达220 mV，为振动能量的收集利用提供了参考依据。
磁控形状记忆合金(MSMA) 振动能量采集器 悬臂梁 样机 有限元分析 magnetically controlled shape memory(MSMA) vibration energy harvester cantilever beam prototype finite element analysis
中国计量科学研究院信息与电子计量科学和测量技术研究所, 北京 100029
针对NTN技术的脉冲波形参数国家基准已无法完全满足目前超高速电脉冲波形测量和校准的现状,构建了基于电光采样技术的脉冲波形参数测量系统,自主设计并制备了钽酸锂基共面波导结构的高频电光调制器,通过网络分析系统测量得到了其3 dB频率响应可达100 GHz。以高速光电探测器输出的电脉冲波形作为待测信号,对系统参数进行了详细的分析和优化。在优化完善的基础上,最终实现了对70 GHz高速光电探测器输出电脉冲波形的精密测量,获得的波形的上升时间和半峰全宽分别为4.6 ps和5.0 ps,这将为我国基于电光采样技术脉冲波形参数国家基准的建立和持续提升提供参考。
计量 脉冲波形 电光采样 上升时间 电光调制
Author Affiliations
Abstract
1 Key Laboratory of Photoelectronic Materials, Ningbo University, Ningbo 315211, China
2 Ningbo Institute of Materials Technology and Engineering, the Chinese Academy of Sciences, Ningbo 315211, China
3 Department of Physics, Dalian Maritime University, Dalian 116026, China
A Ce3+ ion-doped α-NaYF4 single crystal of high quality is grown successfully by an improved flux Bridgman method under the conditions of taking the chemical raw composition of NaF:KF:YF3:CeF3 in the molar ratio of 30∶18∶48∶4, where the KF is shown to be an effective assistant flux. The x ray diffraction, absorption spectra, excitation spectra, and emission spectra of the Ce3+-doped α-NaYF4 single crystal are measured to investigate the phase and optical properties of the single crystals. The absorption spectrum of the Ce3+:α-NaYF4 shows a strong band that peaks at the wavelength of 300 nm. The emission spectrum of the Ce3+:α-NaYF4 emits an intense ultraviolet (UV) band at the wavelength of 332 nm under the excitation of 300 nm light. Two separated luminous bands of 330 and 350 nm, which correspond to the transitions 5d→F5/22 and 5<
160.0160 Materials 230.0230 Optical devices 260.1180 Crystal optics 300.0300 Spectroscopy Chinese Optics Letters
2016, 14(6): 061601
Author Affiliations
Abstract
1 Key Laboratory of Photo-Electronic Materials, Ningbo University, Ningbo 315211, China
2 Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo 315211, China
3 Department of Physics, Dalian Maritime University, Dalian 116026, China
The absorption spectra, excitation spectra, and emission spectra of
Tb3+/Eu3+ ions in
LiYF4 single crystals synthesized by an improved Bridgman method are measured. The emission spectra of several bands, mainly located at blue
～487 nm (
Tb:D45→F76), yellowish green
～542 nm (
Tb:D45→F75), and red
～611 nm (
Eu:D05→F72) wavelengths, are observed under excitation by UV light. An ideal white light emission as a result of simultaneous combination of these emissions can be obtained from 1.11 mol%
160.0160 Materials 230.0230 Optical devices 300.0300 Spectroscopy Chinese Optics Letters
2015, 13(7): 071601
Author Affiliations
Abstract
We report the dark blue nonlinear Cerenkov radiation by the second harmonic generation (SHG) in a two-layer-stacked hexagonal periodically-poled-MgO: LiNbO3s (PPMgOLNs). Based on the direct wafer bonding of two target PPMgOLNs rotating around the axis perpendicular to the plane with an angle of 30o, twelve bright spots as twice of those in a single PPMgOLN are shown at each second-harmonic C erenkov ring. The experimental results agree with the theoretical ones and present a promising application in the fabrication of three-dimensional (3D) PPMgOLNs.
050.1940 Diffraction 190.2620 Harmonic generation and mixing Chinese Optics Letters
2014, 12(3): 030501
Author Affiliations
Abstract
We propose a polarization-insensitive and broadband subwavelength grating reflector based on a multilayer structure. The reflector has an overlapped high reflectivity (>99.5%) bandwidth of 248 nm between the TE and the TM polarizations, which is much higher than the previously reported results. We believe this subwavelength grating reflector can be applied to unpolarized devices.
050.1950 Diffraction gratings 050.5080 Phase shift 050.6624 Subwavelength structures 230.4170 Multilayers Chinese Optics Letters
2014, 12(2): 020502
