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排序方式: 共有146条查询结果,搜索用时 12 毫秒
41.
42.
The He-McKellar-Wilkens (HMW) effect in non-commutative (NC) space is studied. By solving the Dirac equations on NC space, we obtain topological HMW phase in NC space where the additional terms related to the space non-commutativity are given explicitly. 相似文献
43.
为了提高GaN基蓝光LED的光提取效率,本文建立了LED顶面分别铺设ZnO纳米柱和纳米锥结构的两种模型,利用时域有限差分法对两种模型进行仿真并对结果进行了比较.仿真结果表明,ZnO纳米结构的各项几何结构参量(包括排列周期P、高度L、宽度W以及斜率k等),对LED顶端光提取效率影响显著.仿真分别得到了两种结构的最佳模型,通过比较,LED顶面纳米柱和纳米锥结构对光提取效率的提高效果相近,其最佳提取效率分别增强至无任何结构时的2.5倍和2.3倍.同时,通过对各项参量扫描获得的对光提取效率的变化曲线进行了分析,并给出了相应相应的理论解释.这些模型优化和理论分析对实际的高性能GaN基LED的设计制造有着指导意义. 相似文献
44.
非对易相空间中角动量的分裂 总被引:10,自引:0,他引:10
非对易空间效应是一种在弦尺度下出现的物理效应. 本文首先介绍了在Schwinger表象中角动量的3个分量用产生--消灭算符的表示形式, 接着讨论了非对易相空间的量子力学代数; 然后用对易空间谐振子的产生-消灭算符表示出了在非对易情况下的角动量; 最后讨论了非对易相空间中角动量的分裂. 相似文献
45.
46.
A specially designed experiment is performed for investigating gate-induced
drain leakage (GIDL) current in 90nm CMOS technology using lightly-doped
drain (LDD) NMOSFET. This paper shows that the drain bias $V_{\rm D}$ has a
strong effect on GIDL current as compared with the gate bias $V_{\rm G}$ at the
same drain--gate voltage $V_{\rm DG}$. It is found that the difference between
$I_{\rm D}$ in the off-state $I_{\rm D}-V_{\rm G}$ characteristics and the
corresponding one in the off-state $I_{\rm D}-V_{\rm D}$ characteristics, which is
defined as $I_{\rm DIFF}$, versus $V_{\rm DG}$ shows a peak. The difference between
the influences of $V_{\rm D}$ and $V_{\rm G}$ on GIDL current is shown
quantitatively by $I_{\rm DIFF}$, especially in 90nm scale. The difference is
due to different hole tunnellings. Furthermore, the maximum $I_{\rm DIFF
}$($I_{\rm DIFF,MAX})$ varies linearly with $V_{\rm DG}$ in logarithmic coordinates
and also $V_{\rm DG}$ at $I_{\rm DIFF,MAX}$ with $V_{\rm F}$ which is the characteristic
voltage of $I_{\rm DIFF}$. The relations are studied and some related
expressions are given. 相似文献
47.
首先回顾了有磁荷(或等效磁荷)存在的情况下电磁场双四维势的描述方法,给出了场强与双四维势的关系以及具有电磁对偶对称性的Maxwell方程;利用Green函数法求出了场方程具有Lorentz变换协变性的推迟解;最后给出了广义李纳-魏谢尔势的表述形式. 相似文献
48.
Hot-carrier degradation for 90nm gate length LDD-NMOSFET with ultra-thin gate oxide under low gate voltage stress 下载免费PDF全文
The hot-carrier degradation for 90~nm gate length lightly-doped drain
(LDD) NMOSFET with ultra-thin (1.4~nm) gate oxide under the low gate
voltage (LGV) (at Vg=Vth, where Vth is the
threshold voltage) stress has been investigated. It is found that the
drain current decreases and the threshold voltage increases after the
LGV (Vg=Vth stress. The results are opposite to the
degradation phenomena of conventional NMOSFET for the case of this
stress. By analysing the gate-induced drain leakage (GIDL) current
before and after stresses, it is confirmed that under the LGV stress
in ultra-short gate LDD-NMOSFET with ultra-thin gate oxide, the hot
holes are trapped at interface in the LDD region and cannot shorten
the channel to mask the influence of interface states as those in
conventional
NMOSFET do, which leads to the different degradation phenomena from those of the
conventional NMOS devices. This paper also discusses the degradation in the
90~nm gate length LDD-NMOSFET with 1.4~nm gate oxide under the LGV stress at
Vg=Vth with various drain biases. Experimental results show that
the degradation slopes (n) range from 0.21 to 0.41. The value of
n is
less than that of conventional MOSFET (0.5-0.6) and also that of the long gate
length LDD MOSFET (\sim0.8). 相似文献
49.
In this paper we study the bilayer quantum Hall (QH) effect on a noncommutative phase space (NCPS). By using perturbation theory, we calculate the energy spectrum, eigenfunction, Hall current, and Hall conductivity of the bilayer QH system, and express them in terms of noncommutative parameters θ and θ^-, respectively. In our calculation, we assume that these parameters vary from laver to laver. 相似文献
50.