论文标题
掺杂不匹配的合金中的血浆频率
Plasma frequency in doped highly mismatched alloys
论文作者
论文摘要
由于引入合金元件，高度不匹配的合金（HMA）具有强烈修改的带结构。我们认为合金元件的孤立状态在宿主传导带附近，这会导致传导带分为两个带。当通过掺杂，使用基于疾病平均绿色的功能的半分析方法，我们确定低能带的较低能带时的散装等离子体频率。我们包括带间跃迁到高能带的非平凡效应，该效应将等离子频率限制为小于有效的带隙。我们表明，分裂带中的状态分布导致HMA中的等离子与标准金属和半导体中的等离子不同。下部分裂带的有效质量$ m^*$随合金分数而变化，我们发现具有$ \ sqrt {n}/m^*$而不是$ \ sqrt {n/m^*} $的等离子频率$ n $ scales均具有$ \ sqrt {n}/m^*$。我们建议实验以观察这些现象。考虑到这组合金中的典型材料参数范围并以现实的例子为例，我们建议HMA可以用作高度可调的低频等离子体材料。
Highly mismatched alloys (HMAs) have band structures strongly modified due to the introduction of the alloying element. We consider HMAs where the isolated state of the alloying element is near the host conduction band, which causes the conduction band to split into two bands. We determine the bulk plasma frequency when the lower-energy band is partially occupied, as by doping, using a semi-analytical method based on a disorder-averaged Green's function. We include the nontrivial effects of interband transitions to the higher-energy band, which limit the plasma frequency to be less than an effective band gap. We show that the distribution of states in the split bands causes plasmons in HMAs to behave differently than plasmons in standard metals and semiconductors. The effective mass of the lower split band $m^*$ changes with alloy fraction, and we find that the plasmon frequency with small carrier concentration $n$ scales with $\sqrt{n}/m^*$ rather than the $\sqrt{n/m^*}$ that is expected in standard materials. We suggest experiments to observe these phenomena. Considering the typical range of material parameters in this group of alloys and taking a realistic example, we suggest that HMAs can serve as highly tunable low-frequency plasmonic materials.
