排序方式: 共有44条查询结果,搜索用时 78 毫秒
41.
在MgO单晶势垒磁性隧道结中发现的室温高隧穿磁电阻现象,是近些年自旋电子学以及磁性隧道结磁电阻材料研究中的又一重大突破。本文主要评述和介绍2001年以来MgO单晶势垒磁性隧道结第一性原理计算和实验上的重要进展,以及介绍利用Layer-KKR第一性原理计算方法研究的Fe(001)/MgO/Fe、Fe(001)/FeO/MgO/Fe、Fe(001)/Mg/MgO/Fe、Fe(001)/Co/MgO/Co/Fe和Fe(001)/MgO/Fe/MgO/Fe等基于单晶MgO(001)单势垒及双势垒磁性隧道结材料的电子结构和自旋相关输运性质研究的最新进展。这些第一性原理定量计算的结果,不仅从物理上增强了对MgO单晶势垒磁性隧道结的电子结构和自旋相关输运特性的了解,而且对于研究新型室温磁电阻隧道结材料及其在自旋电子学器件中的广泛应用,具有一定的参考价值。 相似文献
42.
利用低功率电弧放电辅助甲烷燃烧,研究了在不同甲烷/空气比例的情况下,等离子体对甲烷燃烧的影响。采用发射光谱仪进行光谱诊断,比较有/无等离子体辅助甲烷燃烧火焰发射光谱的异同,讨论了等离子体辅助燃烧可能发生的过程和机理。比较有/无等离子体辅助甲烷燃烧火焰温度的变化。利用气相色谱和烟气分析仪对甲烷燃烧产物中的CH4、CO 和O2 进行分析。实验结果表明,加等离子体后,火焰的温度升高,尾气中的可燃性成分减少,氧气含量降低,在很大程度上提高了甲烷的燃烧效率;甲烷/空气的比例越低,燃烧效率的提高越明显;甲烷的富燃燃烧极限从16%调高到21%。 相似文献
43.
The ohmic contacts of 4H-SiC are fabricated on nitrogen ion implanted layers made by performing
box-like-profile implantation three and four times. Implantation parameters such as the standard deviation σ and the projection range Rp are calculated by the Monte Carlo simulator TRIM. Ni/Cr ohmic contacts on Si-face 4H-SiC implantation layers are measured by transfer length methods (TLMs). The results show that the values of sheet resistance Rsh are 30~kΩ /□ and 4.9~kΩ/□ and the values of specific contact resistance ρc of ohmic contacts are 7.1× 10-4Ω.cm2 and 9.5× 10-5Ω.cm2 for the implanted layers with
implantation performed three and four times respectively. 相似文献
44.
This paper describes the fabrication and characteristics of the lateral Ti/4H-SiC Schottky barrier diodes (SBDs). SBDs are fabricated by nitrogen ion implantation into p-type 4H-SiC epitaxial layer. The implant depth profile is simulated using the Monte Carlo simulator TRIM. Measurements of the reverse I-V characteristics demonstrate a low reverse current, that is good enough for many SiC-based devices such as SiC metal-semiconductor field-effect transistors, and SiC static induction transistors. The parameters of the diodes are extracted from the forward I-V characteristics. The barrier height φ_b of Ti/4H-SiC is 0.95 eV. 相似文献