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文章基于Fabry-Pérot半导体微腔,阐述了新型元激发--激子极化激元的基本概念和微观描述,讨论了其在光学放大器、光学开关和单光子源方面的潜在应用,概述了对其实现Bose-Einstein凝聚的实验研究,最后对将来的发展做了一个简单的展望. 相似文献
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We present a numerical study on the pattern formation in a two-dimensional vibrated granular layer by a molecular dynamics algorithm.Through analysing the granular density distribution,we can explore the inner movement process of particles.It is confirmed that there are a dispersive regime and a saturation regime for frequency dependence,between which a critical frequency exists,It is found that there is another saturation regime for thickness dependence,The wavelength increases with increasing layer thickness,but there is a critical thickness after which the wavelength is unchanged. 相似文献
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凝聚态物理学的新进展Ⅱ 总被引:5,自引:1,他引:4
本文综述了凝聚态物理学近年来的重要进展,并举出若干例子予以阐述。第Ⅱ部分主要关注的问题为非周期结构与低维体系的物理学。讨论的课题包括:无序体系中经典波的局域化;分形结构的动力学行为;准周期结构的能谱;量子霍尔效应;二维熔化;有机导体与超导体。 相似文献
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从实验和理论上阐述了氧空位对Co掺杂ZnO半导体磁性能的影响.采用磁控溅射法在不同的氧分压下制备了Zn095Co005O薄膜,研究了氧分压对薄膜磁性能的影响.实验结果表明,高真空条件下制备的Zn095Co005O薄膜具有室温铁磁性,提高氧分压后制备的薄膜铁磁性逐渐消失.第一性原理计算表明,在Co掺杂ZnO体系中引入氧空位有利于降低铁磁态的能量,铁磁态的稳定性与氧空位和Co之间的距离密切相关.
关键词:
Co掺杂ZnO
稀磁半导体
第一性原理计算
氧空位缺陷 相似文献
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凝聚态物理学已经成为当代物理学中最重要和最丰产的分支学科 .它的特征在于研究人员众多 ,研究成果丰富多彩 ,对技术发展影响广泛 ,与其他学科相互渗透迅速 .从历史来看 ,凝聚态物理学是由固体物理学逐渐演变而来的 .但是 ,由于人们对两者的学科分界缺乏明晰的认识 ,再加上不熟悉凝聚态物理学所引入的用以统一理论框架的新概念体系 ,因而 ,虽然已有不少优秀的固体物理学教科书对于凝聚态物理学的教材也有一些卓有特色的尝试 ,但覆盖全面且条理清晰、便于理解的凝聚态物理学入门教科书尚付阙如 .这一令人遗憾的情况特别清楚地表现在传统的固… 相似文献
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本文系统地综述在不同类型的无序固体中发现的低温反常性质,并用隧道态模型进行详细的理论分析,对于有关的微观图象和存在的问题也作扼要的讨论。 相似文献
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Interface-induced topological phase and doping-modulated bandgap of two-dimensioanl graphene-like networks
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Ningjing Yang 《中国物理 B》2023,32(1):17201-017201
Biphenylene is a new topological material that has attracted much attention recently. By amplifying its size of unit cell, we construct a series of planar structures as homogeneous carbon allotropes in the form of polyphenylene networks. We first use the low-energy effective model to prove the topological three periodicity for these allotropes. Then, through first-principles calculations, we show that the topological phase has the Dirac point. As the size of per unit cell increases, the influence of the quaternary rings decreases, leading to a reduction in the anisotropy of the system, and the Dirac cone undergoes a transition from type II to type I. We confirm that there are two kinds of non-trivial topological phases with gapless and gapped bulk dispersion. Furthermore, we add a built-in electric field to the gapless system by doping with B and N atoms, which opens a gap for the bulk dispersion. Finally, by manipulating the built-in electric field, the dispersion relations of the edge modes will be transformed into a linear type. These findings provide a hopeful approach for designing the topological carbon-based materials with controllable properties of edge states. 相似文献