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排序方式: 共有1274条查询结果,搜索用时 15 毫秒
91.
纳磁逻辑电路具有低功耗、非易失和可常温下制备等优点, 实现低功耗片上时钟是其集成化的必备条件. 本文提出了一种基于交换作用的纳磁逻辑电路片上时钟结构, 用载流铜导线产生的奥斯特场将铁磁体薄膜覆层进行磁化, 然后依靠铁磁体层与纳磁体界面存在的交换作用场使后者磁化方向发生翻转. 与轭式铁磁体时钟用外磁场控制纳磁体磁化方向相比, 该方案在功耗方面降低了5/6, 时钟边界杂散场强度降低了2/3, 达到降低功耗、减轻串扰的目的. 此外, 采用微磁仿真进一步验证了该时钟结构上的纳磁体逻辑阵列可以实现逻辑功能.
关键词:
纳磁逻辑
片上时钟
交换作用 相似文献
92.
93.
通过分析大学物理互动教学的必要性及意义,结合自身的教学实践及兄弟单位的有关经验,探讨了大学物理互动教学的几种模式,认为:大学物理互动教学有利于体现教学以学生为主体的思想,有利于提高学生学习大学物理的积极性及主动性,大学物理互动教学法是一种值得推广的教学方法。 相似文献
94.
The production of the three normal neutrinos via e-e+ collision at Z-boson peak(neutrino production in a Z-factory) is investigated thoroughly. The differences of νe-pair production from νμ-pair and ντ-pair production are presented in various aspects. Namely the total cross sections, relevant differential cross sections and the forwardbackward asymmetry etc. for these neutrinos are presented in terms of figures as well as numerical tables. The restriction on the room for the mixing of the three species of light neutrinos with possible externals(heavy neutral leptons and/or sterile neutrinos) from refined measurements of the invisible width of Z-boson is discussed. 相似文献
95.
We report the dark blue nonlinearˇCerenkov 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 30°,twelve bright spots as twice of those in a single PPMgOLN are shown at each second-harmonicˇCerenkov ring.The experimental results agree with the theoretical ones and present a promising application in the fabrication of three-dimensional(3D)PPMgOLNs. 相似文献
96.
Study on lattice vibrational properties and Raman spectra of Bi_2Te_3 based on density-functional perturbation theory 下载免费PDF全文
We present a variational density-functional perturbation theory(DFPT) to investigate the lattice dynamics and vibrational properties of single crystal bismuth telluride material. The phonon dispersion curves and phonon density of states(DOS) of the material were obtained. The phonon dispersions are divided into two fields by a phonon gap. In the lower field,atomic vibrations of both Bi and Te contribute to the DOS. In the higher field, most contributions come from Te atoms. The calculated Born effective charges and dielectric constants reveal a great anisotropy in the crystal. The largest Born effective charge generates a significant dynamic charge transferring along the c axis. By DFPT calculation, the greatest LO–TO splitting takes place in the infrared phonon modes and reaches 1.7 THz in the Brillouin zone center. The Raman spectra and peaks corresponding to respective atomic vibration modes were found to be in good agreement with the experimental data. 相似文献
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98.
A diode end-pumped self-Q-switched Cr,Nd:YAG laser was established with pulse duration in the range of 8-10ns. The maximum average output power was 4.4 W and the slope efficiency was 27% using an output coupler of R=70%. At pumping power of 17.4 W the laser produces high-quality pulses at 1064 nm in a TEMoo-mode. 相似文献
99.
100.
Antiphase State in Passively Q-Switched Yb:YAG Microchip Lasers with a Nd,Cr:YAG as Saturable Absorber 下载免费PDF全文
We experimentally investigate the antiphase dynamics phenomenon that occurs in a diode-pumped passively Q-switched Yb:YAG multimode laser with a Nd,Cr:YAG saturable absorber. Due to the effect of spatial hole burning, the multimode lasers with one, two, or three modes at different pump power are observed, and the pulses sequences display classic antiphase dynamics. 相似文献