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1.
都有为 《物理》2011,40(12):823
乞借贵刊一角,以对石墨烯、富勒烯的译名提出异意,愿与物理学界、化学界、材料科学界学者们切磋之. Graphene名词因发明者A.Geim和K.Novoselov获2010年诺贝尔物理奖而享誉环球.从物理学观点来看,它仅仅是单层或少层石墨片,或者可表述为纯碳原子所构成的石墨单层结构的二维薄膜.它具有特殊的无能隙能带结构,  相似文献   

2.
Graphene因其优异的物理性能和潜在的应用前景,引起物理界和化学界的广泛关注,成为继碳纳米管后凝聚态物理和材料科学领域中又一研究热点,文章详细介绍了近几年发展起来的Graphene的溶液制备方法,例如石墨插层法、液相分散法、氧化石墨还原法、溶剂热法、芳香偶联法等,并对各种方法的特点进行了评述.  相似文献   

3.
Graphene具有优异的电学性质,是非常有前途的纳米电子材料,有希望替代硅成为下一代集成电路材料,尽管目前有很多种制备Graphene的方法,但就Graphene在将来集成电路方面的应用而言,在碳化硅上的外延生长法最具潜力,文章首先从Graphene的能带结构开始,简单介绍为什么Graphene具有诸多优异的电学性质,比如异常霍尔效应、室温下的高迁移率、碳纳米管的弹道输运等,然后介绍这种外延生长方法及其发展现状,通过比较在不同碳化硅晶面和在不同条件下生长的Graphene的表面形貌,得出结论,在加热炉内,生长在碳化硅晶体碳面的Graphene拥有特别高的质量,最后文章着重讨论对碳面Graphene的电学表征实验,这些实验证明这种材料中的电子是狄拉克电子,同时也发现材料具有优异的电学性质.  相似文献   

4.
Physics of the Solid State - Dispersion properties of surface plasmon polaritons in a semiconductor film with graphene plates in the far-IR range and the possibility of controlling propagation...  相似文献   

5.
Graphene是一种严格的二维晶体材料,因其具有独特的结构和性能,已迅速成为国际新材料领域的研究前沿和热点,文章详细介绍了近几年发展起来的Graphene的化学制备方法,如SiC高温热解外延法、过渡金属催化外延法、化学修饰分散/还原法等,并对各种方法的特点,研究现状及应用前景进行了评述.  相似文献   

6.
Graphene的物理性质与器件应用   总被引:1,自引:0,他引:1  
Graphene因其新奇的物理性质和广泛的应用前景已迅速成为国际新材料领域的研究前沿和热点.文章详细介绍了Graphene奇特的物理性质(多体相互作用、量子霍尔效应、双极场效应、弱局域化效应等),并对其在微纳米器件、分子电子学、自旋电子学等领域的应用进展给出了综述.  相似文献   

7.
云中客 《物理》2008,37(4):278
内禀电子迁移率(intrinsicelectronmobility)是测定电子在晶格中移动难易程度的一个物理参数,它的单位为cm^2/Vs.它又是使半导体装置能否小型化与快速运行的重要依据、最近由英国Manchester大学G.Gein教授为首的跨国(包括俄罗斯、荷兰和美国)科学家组成的研究组进行了一项极有成效的工作,他们发现二维石墨烯薄层(只有一个原子大小的厚度)半导体的内禀电子迁移率高达200,000cm^2/Vs,这要比硅半导体的内禀电子迁移率(1500cm^2/Vs)高100倍,比砷化镓(8500cm^2/Vs)高20倍。  相似文献   

8.
Physics of the Solid State - The Young’s modulus of a finite-sized zigzag carbon nanotube-based ribbon-like columnar graphene is theoretically studied. The dependence of elastic...  相似文献   

9.
10.
Physics of the Solid State - It was found that an insignificant increase of the concentration of carbon atoms in the volume of metal (~2–3%) leads to a significant increase (by 3–4...  相似文献   

11.
Ma J  Xie GQ  Lv P  Gao WL  Yuan P  Qian LJ  Yu HH  Zhang HJ  Wang JY  Tang DY 《Optics letters》2012,37(11):2085-2087
We experimentally demonstrated a passively mode-locked femtosecond laser by using a graphene-based saturable absorber mirror (graphene SAM) in the spectral region of 2 μm. The graphene SAM was fabricated by transferring chemical-vapor-deposited, high-quality, and large-area graphene on a highly reflective plane mirror. Stable mode-locked laser pulses as short as 729 fs were obtained with a repetition rate of 98.7 MHz and an average output power of 60.2 mW at 2018 nm.  相似文献   

12.
王肖沐  甘雪涛 《中国物理 B》2017,26(3):34203-034203
Graphene and other two-dimensional materials have recently emerged as promising candidates for next-generation,high-performance photonics. In this paper, the progress of research into photodetectors and other electro-optical devices based on graphene integrated silicon photonics is briefly reviewed. We discuss the performance metrics, photo-response mechanisms, and experimental results of the latest graphene photodetectors integrated with silicon photonics. We also lay out the unavoidable performance trade-offs in meeting the requirements of various applications. In addition, we describe other opto-electronic devices based on this idea. Integrating two-dimensional materials with a silicon platform provides new opportunities in advanced integrated photonics.  相似文献   

13.
本文利用第一原理方法计算了空位缺陷和硼(B)掺杂时对Pt在graphene上吸附的影响.结果表明:Pt在graphene上吸附的稳定位置是Pt吸附在桥位;悬挂键的存在极大的增强了Pt在graphene空位处的吸附;B替位掺杂有利于Pt原子在杂质附近的吸附.  相似文献   

14.
Particular features of waveguide propagation of modes in a planar structure that consists of alternating layers of a dielectric and graphene are investigated. Within the effective-medium approximation, dispersion relations are obtained for symmetric and antisymmetric waveguide modes. Based on their numerical analysis, the frequency dependences of the propagation and decay constants, of the group and phase velocities, and of the energy flux carried by waveguide modes are constructed. The influence of the fraction of graphene in the structure on the behavior of waveguide modes is analyzed.  相似文献   

15.
In the field of optoelectronics, circular dichroism (CD) has caused great research interest because it is widely used in imaging and biosensing. A new method for dynamically controlling terahertz (THz) CD in metamaterials is proposed. By introducing chirality and graphene to metamaterials, a pair of chiral structures with completely opposite responses to left-handed circularly polarized (LCP) waves and right-handed circularly polarized (RCP) waves are designed. The influencing factors of CD are explored, including the gap of the structure, the linewidth of graphene, and the Fermi level of graphene. The largest CD (ΔR) is 77%. The CD can be actively modulated in a modulation range of 39–77% and the modulation depth is up to 38%. In addition, two-channel and four-channel chiral metasurfaces for near-field imaging are designed in this way. Good imaging effects and on (“1”) or off (“0”) effects of the multichannel metasurface are demonstrated. This work provides new ideas for the design of tunable metasurfaces and promotes the application of metasurfaces in THz dynamic imaging.  相似文献   

16.
本文利用第一原理方法计算了空位缺陷和硼(B)掺杂时对Pt在graphene上吸附的影响.结果表明:Pt在graphene上吸附的稳定位置是Pt吸附在桥位;悬挂键的存在极大的增强了Pt在graphene空位处的吸附;B替位掺杂有利于Pt原子在杂质附近的吸附.  相似文献   

17.
New nanomeshes with closed holes based on bilayer graphene twisted by 30° are studied. It is found that such structures can have different electronic characteristics (from semiconducting to metallic) depending on the shape of holes. Comparison with the single-layer graphene meshes having holes of similar shapes demonstrates a significant difference of their electronic spectra. The meshes with triangular “folded” holes turn out to be nonmagnetic in contrast to the single-layer meshes with the same holes. The spectra of 30° bilayer graphene nanomeshes exhibit numerous peaks in the electron density of states within a wide energy range. This makes such structures promising for applications in photovoltaics and optoelectronics. Features of 30° Moiré Graphene Bilayers with Folded Holes.  相似文献   

18.
Two new derivatives of phosphatidylcholine with an intramolecularly quenched fluorescence, namely, 1––bromoundecanoyl–2–[4–(pyren–1–yl)butyroyl]–sn–glycero–3–phosphocholine (BPPhC) and 1–(9,10–dibromostearoyl)–2–[4–(pyren–1–yl)butyroyl]–sn–glycero–3–phosphocholine (DBPPhC), have been obtained by replacing acyl chains by residual pyrenebutyric and bromine–labeled fatty acids. Their structure has been verified by the 1H–NMR method and the spectral properties have been characterized in media of different polarity with the aid of absorption and fluorescent spectroscopy. It has been established that when BPPhC and DBPPhC are included in liposomes, the intensity of their fluorescence changes markedly as a function of the physical state of the bilayer, which makes it possible to use the compounds obtained as lipid probes for investigating the properties of biological and artificial membranes.  相似文献   

19.
用激光荧光法研究了pyrene(芘,嵌二萘)在SiO_2表面上生成excimer(激基缔合物)的机理。在4.2°K温度下,分别用330nm和375nm的激光激发pyrene,可检测到不同的荧光光谱带;在77°K时,分别在392nm和475nm处检测pyrene在SiO_2表面上的激发光谱,也得到不同的激发谱带;说明在实验样品条件下,pyrene在SiO_2表面上有稳定的“静态”eimer存在,当激发这些eimer时,就生成excimer,从而可在475nm附近观察到excimer的特征发射带。然而,不同温度下的荧光光谱又显示出,pyrene吸附在SiO_2表面上除去由dimer受激而直接生成的excimer外,仍有部分“动态”的excimer生成,即由受激的单体pyrene分子在表面通过扩散而和另一个单体pyrene分子形成excimer(就象在溶液中一样)。  相似文献   

20.
We perform a first-principles calculation based on density functional theory to investigate the interface between single layer graphene and metal oxides. Our study reveals that the monolayer graphene becomes semiconducting by single crystal SiO2 and Al2O3 contact, with energy gaps to - 0.9 and - 1.8 eV, respectively. We find the gap originates from the breakage of π bond integrity, whose extent is related to the interface atom configuration. We believe that our results highlight a promising direction for the feasibility to apply large scale graphene layers as building blocks in future electronics devices.  相似文献   

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