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31.
32.
镜面起伏对1.55μm Si基MEMS光滤波器的影响 总被引:6,自引:0,他引:6
用传输矩阵方法,在简化的光学模型基础上,分别讨论了分布式Bragg反射镜DBR(Distributed Bragg Reflector)的生长精度及镜面起伏对1.55 μm Si基MEMS(Micro-Electro-Mechanical-System)可调谐光滤波器透射谱的影响.计算表明:DBR生长误差仅使主透射峰位置发生变化,而镜面起伏是导致主透射峰性能劣化的主要原因,它使得FWHM增大,透射峰强度下降.理论计算结果能较好地解释实验现像.在此基础上,进一步讨论了引起镜面起伏的多种原因,并提出了可能的解决方法. 相似文献
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34.
硅锗异质结双极晶体管(SiGe HBT)一般以重掺硼(B)的应变SiGe层作为基区.精确表征SiGe材料能带结构对SiGe HBT的设计具有重要的意义.在应变SiGe材料中,B的重掺杂一方面会因为重掺杂效应使带隙收缩,另一方面,B的引入还会部分补偿Ge引起的应变,从而改变应变引起的带隙变化.在重掺B的应变SiGe能带结构研究中,采用半经验方法,考虑了B的应变补偿作用对能带的影响,对Jain-Roulston模型进行修正,并分析了重掺杂引起的带隙收缩在导带和价带的分布. 相似文献
35.
In this paper, we introduced the dressed exciton model of the semiconductor micro-cavity device. In the semiconductor micro cavity of vertical-cavity surface-emission device, the excitons first coupled with the cavity through an intra-electromagnetic field and formed the dressed excitons. Then these dressed excitons decayed into the vacuum cavity optical mode, as a multi-particle process. Through the quantum electrodynamics method, the dipole emission density and system energy decayed equation were obtained. And it was predicted that the excitons decay into a very narrow mode when the exciton-cavity coupling becomes strong enough. 相似文献
36.
37.
A 2× 2 electro-optic switch is experimentally demonstrated
using the optical structure of a Mach--Zehnder interferometer (MZI) based
on a submicron rib waveguide and the electrical structure of a PIN diode on
silicon-on-insulator (SOI). The switch behaviour is achieved through
the plasma dispersion effect of silicon. The device has a modulation arm
of 1~mm in length and cross-section of 400~nm× 340~nm. The
measurement results show that the switch has a VπLπ
figure of merit of 0.145~V\cdot cm and the extinction ratios of two
output ports and cross talk are 40~dB, 28~dB and -28~dB,
respectively. A 3~dB modulation bandwidth of 90~MHz and a switch
time of 6.8~ns for the rise edge and 2.7~ns for the fall edge are also
demonstrated. 相似文献
38.
Si nanopillar arrays with nanocrystals produced by template-induced growth at room temperature 下载免费PDF全文
Well-aligned and closely-packed silicon nanopillar (SNP) arrays are fabricated by using a simple method with magnetron sputtering of Si on a porous anodic alumina (PAA) template at room temperature. The SNPs are formed by selective growth on the top of the PAA pore walls. The growth mechanism analysis indicates that the structure of the SNPs can be modulated by the pore spacing of the PAA and the sputtering process and is independent of the wall width of the PAA. Moreover, nanocrystals are identified by using transmission electron microscopy in the as-deposited SNP samples, which are related to the heat isolation structure of the SNPs. The Raman focus depth profile reveals a high crystallization ratio on the surface. 相似文献
39.
InP-based evanescently coupled high-responsivity photodiodes with extremely low dark current density integrated diluted waveguide at 1550 nm 下载免费PDF全文
In this paper, we have demonstrated a high performance waveguide photodiode integrated diluted waveguide serving as a fibre-to-waveguide coupler to achieve high coupling efficiency. High responsivity (> 1 A/W), high saturation power (> 45 mA) in the static state and extremely low dark current density (0.04 pA/μm2) with 3 dB bandwidth at 13.4 GHz have been achieved. 相似文献
40.