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991.
利用X 射线衍射(XRD)和X射线吸收精细结构(XAFS)方法研究了磁控共溅射方法制备的MnxGe1-x薄膜样品的结构随掺杂磁性原子Mn含量的变化规律.XRD结果表明,在Mn的含量较低(7.0%)的Mn0.07Ge0.93样品中,只能观察到对应于多晶Ge的XRD衍射峰,而对Mn含量较高(25.0%, 36.0%)的Mn0.25Ge0.75和Mn关键词:
磁控溅射
XRD
XAFS
xGe1-x稀磁半导体薄膜')" href="#">MnxGe1-x稀磁半导体薄膜 相似文献
992.
A novel compact supercontinuum (SC) source using the single mode photonic crystal fibers (PCF) pumped with an all fiber MOPA
fiber laser is demonstrated experimentally. A bandwidth of 700 nm is achieved by operating the pumping fiber laser at a wavelength
of 1064 nm, pulse duration of 10 ns, repetition rate of 50 kHz and peak power of 1 kW. The SC generation is initiated through
modulation instability (MI) which breakups the nanosecond pump pulses into picosecond or femtosecond pulses, and further broadened
through nonlinear effects of PCF. 相似文献
993.
Zhanmin Zhu 《数学研究》2021,54(4):451-459
Let $I$ be an ideal of a ring $R$. We call $R$ weakly $I$-semiregular if $R$/$I$ is a von Neumann regular ring. This definition generalizes $I$-semiregular rings. We give a series of characterizations and properties of this class of rings. Moreover, we also give some properties of $I$-semiregular rings. 相似文献
994.
995.
H. B. Zhu H. X. Ge L. Y. Dong S. Q. Dai 《The European Physical Journal B - Condensed Matter and Complex Systems》2007,57(1):103-108
Based on the Nagel-Schreckenberg (NaSch)
model of traffic flow, a modified cellular automaton (CA) traffic
model with the density-dependent randomization (abbreviated as the
DDR model) is proposed to simulate traffic flow. The fundamental
diagram obtained by simulation shows the ability of this modified
NaSch model to capture the essential features of traffic flow,
e.g., synchronized flow, metastable state, hysteresis and phase
separation at higher densities. Comparisons are made between this
DDR model and the NaSch model, also between this DDR model and the
VDR model. And the underlying mechanism is analyzed. All these
results indicate that the presented model is reasonable and more
realistic. 相似文献
996.
We study theoretically the properties of a thin film of a semiconductor embedded in the interface of two kinds of single-negative materials. At some frequencies the structure with suitable size is equivalent to an effective (near) zero-index medium. The coupling of exciton resonance in the semiconductor and the interface mode in a zero-index medium leads to Rabi splitting. Compared with Rabi splitting observed in cavities, the splitting modes in zero-index media are robust against the scaling change of the length and direction of incident wave. 相似文献
997.
强外加电场与大调制度下光折变动力学光栅形成研究 总被引:1,自引:0,他引:1
强外加电场与大调制度在光折变效应的研究中已经得到了广泛应用。采用PDECOL算法,严格求解光折变带输运方程,得到外加电场时不同调制度下光折变晶体中随时间变化的空间电荷场、载流子浓度,并讨论了外加电场对它们的影响。通过将物质方程与耦合波方程联立数值求解,可得到光折变光栅形成过程中两波耦合增益系数以及光束条纹相位的变化。模拟结果表明,在强外加电场作用下,两束记录光之间的光强与相位耦合都得到了增强,而原有的解析式忽视了强外加电场与大调制度对空间电荷场相位耦合的影响,此时不再适用。同时发现折射率光栅与记录光束条纹均发生弯曲,并不再保持平行。 相似文献
998.
对描述双掺杂晶体非挥发性全息记录动力学过程的Kukhtarev方程进行了矢量分析,分析中考虑了体光生伏特效应和外加电场的作用。在小信号近似的基础上给出了双中心全息记录中记录与固定阶段空间电荷场的矢量解析解。在综合考虑空间电荷场的各向异性以及晶体有效电光系数的各向异性后,给出了双中心全息记录的优化记录方向。结果表明,对(Fe,Mn)∶LiNbO3晶体633nm寻常光记录,优化记录方向主要由有效电光系数决定,光栅波矢与光轴夹角为22°,方位角为30°;对(Fe,Mn)∶LiNbO3晶体633nm非寻常光记录,优化记录方向主要由固定空间电荷场决定,光栅波矢与光轴夹角为44°,方位角为90°。 相似文献
999.
1000.
Ab initio calculations on the spectroscopic constants, vibrational levels and classical turning points for the 21∏u state of dimer 7Li2 下载免费PDF全文
The accurate dissociation energy and harmonic frequency for the highly excited 2^1Пu state of dimer ^7Li2 have been calculated using a symmetry-adapted-cluster configuration-interaction method in complete active space. The calculated results are in excellent agreement with experimental measurements. The potential energy curves at numerous basis sets for this state are obtained over a wide internuclear separation range from about 2.4a0 to 37.0a0. And the conclusion is gained that the basis set 6-311++G(d,p) is a most suitable one. The calculated spectroscopic constants De, Re, ωe, ωeχe, ae and Be at 6-311++G(d,p) are 0.9670 eV, 0.3125 nm, 238.6 cm^-1, 1.3705 cm^-1, 0.0039 cm^-1 and 0.4921 cm^-1, respectively. The vibrational levels are calculated by solving the radial SchrSdinger equation of nuclear motion. A total of 53 vibrational levels are found and reported for the first time. The classical turning points have been computed. Comparing with the measurements, in which only the first nine vibrational levels have been obtained so far, the present calculations are very encouraging. A careful comparison of the present results of the parameters De and We with those obtained from previous theories clearly shows that the present calculations are much closer to the measurements than previous theoretical results, thus representing an improvement on the accuracy of the ab initio calculations of the potentials for this state. 相似文献