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111.
在采用自旋反转模型分析垂直腔面发射激光器(VCSELs)动力学行为的过程中,为了正确预测VCSELs的动力学行为,需要准确给出自旋反转模型中光场衰减速率k、总反转载流子衰减速率γN、线性二向色性系数γa、线性双折射系数γp、自旋反转速率γs和线宽增强因子α这6个特征参量.本文对1550 nm VCSELs在自由运行和平行光注入下的输出特性进行实验分析,获取了这6个特征参量的值,并着重研究了当激光器温度在10.00–30.00 ℃范围内变化时,这6个特征参量呈现的变化趋势.研究结果表明,随着温度的逐渐升高,γp整体呈现逐渐增加的趋势,γa,γs,γN和k呈现复杂的变化趋势,而α则呈现逐渐减小的趋势. 相似文献
112.
随着传统实验教学模式固有弊端的凸显,因材施教、分层教学的开放性实验教学模式已成为实验教学的发展方向.然而由于开放性实验教学改革所面临的困难短期内无法克服,更多地停留在口号层面上,而无实质性进展.本文在开放性实验教学思想的指导下,采用开放式实验教学与传统实验教学相结合的方法探索了一条更符合认知规律且与实际相适应的有限开放性实验教学方式,给出了部分供同行参考的设计性、研究性实验题目.首次提出了“开放度”的概念,并建议将实验教学的开放度作为重要指标列入高校教学水平评估和实验室评估的评估体系. 相似文献
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提出了一类多线程并行、组合了光滑化与局部重连操作的四面体网格优化算法。采用传统的基于拓扑的数据分解策略实现了并行光滑化算法,利用图染色算法将待光滑化的点分解成多个独立点集。同时提出将一类基于几何的数据分解策略应用于局部重连操作的并行化,在每个局部重连操作涉及的几何区域中定义一个特征点,然后沿希尔伯特(Hilbert)曲线对特征点进行排序,曲线的均匀分解对应局部重连操作在各线程的分配。这一分配策略的优点是使并行执行局部重连操作时重连区域相互干涉的情形极少出现。因此,当干涉情形出现时,可选择放弃产生干涉的操作,并行优化效率和效果并无明显的负面影响。最后,数值实验验证了本文算法的效率和有效性。 相似文献
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Morphological and structural damage investigation of nanostructured molybdenum fuzzy surface after pulsed plasma bombardment 下载免费PDF全文
Yu-Chuan Luo 《中国物理 B》2022,31(4):45203-045203
Steady high-flux helium (He) plasma with energy ranging from 50 eV to 90 eV is used to fabricate a fiber-form nanostructure called fuzz on a polycrystalline molybdenum (Mo) surface. Enhanced hydrogen (H) pulsed plasma in a wide power density range of 12 MW/m2-35 MW/m2 is subsequently used to bombard the fuzzy Mo, thereby simulating the damage of edge localized mode (ELM) to fuzz. The comparisons of surface morphologies, crystalline structures, and optical reflectivity between the original Mo and the Mo treated with various He+ energy and transient power densities are performed. With the increase of He ion energy, the Mo nano-fuzz evolved density is enlarged due to the decrease of filament diameter and optical reflectivity. The fuzz-enhanced He release should be the consequence of crystalline growth and the lattice shrinkage inside the Mo-irradiated layers (~200 nm). The fuzz induced by lower energy experiences more severe melting damage and dust release under the condition of the identical transient H plasma-bombardment. The H and He are less likely to be trapped due to aggravated melting evidenced by the enhanced crystalline size and distinct lattice shrinkage. As the transient power density rises, the thermal effect is enhanced, thereby causing the fuzz melting loss to aggravate and finally to completely disappear when the power density exceeds 21 MW/m2. Irreversible grain expansion results in huge tensile stress, leading to the observable brittle cracking. The effects of transient thermal load and He ion energy play a crucial role in etching Mo fuzz during ELM transient events. 相似文献
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Although hot carriers induced degradation of NMOSFETs has been studied for decades, the role of hot electron in this process is still debated. In this paper, the additional substrate hot electrons have been intentionally injected into the oxide layer to analyze tile role of hot electron in hot carrier degradation. The enhanced degradation and the decreased time exponent appear with the injected hot electrons increasing, the degradation increases from 21.80% to 62.00% and the time exponent decreases from 0.59 to 0.27 with Vb decreasing from 0 V to -4 V, at the same time, the recovery also becomes remarkable and which strongly depends on the post stress gate bias Vg. Based on the experimental results, more unrecovered interface traps are created by the additional injected hot electron from the breaking Si-H bond, but the oxide trapped negative charges do not increase after a rapid recovery. 相似文献
119.
Effect of supply voltage and body-biasing on single-event transient pulse quenching in bulk fin field-effect-transistor process 下载免费PDF全文
Charge sharing is becoming an important topic as the feature size scales down in fin field-effect-transistor(Fin FET)technology. However, the studies of charge sharing induced single-event transient(SET) pulse quenching with bulk Fin FET are reported seldomly. Using three-dimensional technology computer aided design(3DTCAD) mixed-mode simulations,the effects of supply voltage and body-biasing on SET pulse quenching are investigated for the first time in bulk Fin FET process. Research results indicate that due to an enhanced charge sharing effect, the propagating SET pulse width decreases with reducing supply voltage. Moreover, compared with reverse body-biasing(RBB), the circuit with forward body-biasing(FBB) is vulnerable to charge sharing and can effectively mitigate the propagating SET pulse width up to 53% at least.This can provide guidance for radiation-hardened bulk Fin FET technology especially in low power and high performance applications. 相似文献
120.