Related Research Articles
Chemical vapor deposition (CVD) is a vacuum deposition method used to produce high-quality, and high-performance, solid materials. The process is often used in the semiconductor industry to produce thin films.
In physics, a plasmon is a quantum of plasma oscillation. Just as light consists of photons, the plasma oscillation consists of plasmons. The plasmon can be considered as a quasiparticle since it arises from the quantization of plasma oscillations, just like phonons are quantizations of mechanical vibrations. Thus, plasmons are collective oscillations of the free electron gas density. For example, at optical frequencies, plasmons can couple with a photon to create another quasiparticle called a plasmon polariton.
Graphene is an allotrope of carbon consisting of a single layer of atoms arranged in a hexagonal lattice nanostructure. The name is derived from "graphite" and the suffix -ene, reflecting the fact that the graphite allotrope of carbon contains numerous double bonds.
The fractional quantum Hall effect (FQHE) is a physical phenomenon in which the Hall conductance of 2-dimensional (2D) electrons shows precisely quantized plateaus at fractional values of , where e is the electron charge and h is the Planck constant. It is a property of a collective state in which electrons bind magnetic flux lines to make new quasiparticles, and excitations have a fractional elementary charge and possibly also fractional statistics. The 1998 Nobel Prize in Physics was awarded to Robert Laughlin, Horst Störmer, and Daniel Tsui "for their discovery of a new form of quantum fluid with fractionally charged excitations" The microscopic origin of the FQHE is a major research topic in condensed matter physics.
Sankar Das Sarma is an India-born American theoretical condensed matter physicist, who has worked in the broad research topics of theoretical physics, condensed matter physics, statistical mechanics, quantum physics, and quantum information. He has been a member of the department of physics at University of Maryland, College Park since 1980.
Graphene nanoribbons are strips of graphene with width less than 100 nm. Graphene ribbons were introduced as a theoretical model by Mitsutaka Fujita and coauthors to examine the edge and nanoscale size effect in graphene.
Philip Kim is a South Korean physicist. He is a condensed matter physicist known for study of quantum transport in carbon nanotubes and graphene, including observations of quantum Hall effects in graphene.
David R. Nelson is an American physicist, and Arthur K. Solomon Professor of Biophysics, at Harvard University.
Silicene is a two-dimensional allotrope of silicon, with a hexagonal honeycomb structure similar to that of graphene. Contrary to graphene, silicene is not flat, but has a periodically buckled topology; the coupling between layers in silicene is much stronger than in multilayered graphene; and the oxidized form of silicene, 2D silica, has a very different chemical structure from graphene oxide.
The Centre for Advanced 2D Materials (CA2DM), at the National University of Singapore (NUS), is the first centre in Asia dedicated to graphene research. The centre was established under the scientific advice of two Nobel Laureates in physics – Prof Andre Geim and Prof Konstantin Novoselov - who won the 2010 Nobel Prize in Physics for their discovery of graphene. It was created for the conception, characterization, theoretical modeling, and development of transformative technologies based on two-dimensional crystals, such as graphene. In 2019, Prof Konstantin Novoselov moved to Singapore and joined NUS as Distinguished Professor of Materials Science and Engineering.
Transition-metal dichalcogenide (TMD or TMDC) monolayers are atomically thin semiconductors of the type MX2, with M a transition-metal atom (Mo, W, etc.) and X a chalcogen atom (S, Se, or Te). One layer of M atoms is sandwiched between two layers of X atoms. They are part of the large family of so-called 2D materials, named so to emphasize their extraordinary thinness. For example, a MoS2 monolayer is only 6.5 Å thick. The key feature of these materials is the interaction of large atoms in the 2D structure as compared with first-row transition-metal dichalcogenides, e.g., WTe2 exhibits anomalous giant magnetoresistance and superconductivity.
In materials science, the term single-layer materials or 2D materials refers to crystalline solids consisting of a single layer of atoms. These materials are promising for some applications but remain the focus of research. Single-layer materials derived from single elements generally carry the -ene suffix in their names, e.g. graphene. Single-layer materials that are compounds of two or more elements have -ane or -ide suffixes. 2D materials can generally be categorized as either 2D allotropes of various elements or as compounds.
Germanene is a material made up of a single layer of germanium atoms. The material is created in a process similar to that of silicene and graphene, in which high vacuum and high temperature are used to deposit a layer of germanium atoms on a substrate. High-quality thin films of germanene have revealed unusual two-dimensional structures with novel electronic properties suitable for semiconductor device applications and materials science research.
Band-gap engineering is the process of controlling or altering the band gap of a material. This is typically done to semiconductors by controlling the composition of alloys, constructing layered materials with alternating compositions, or by inducing strain either epitaxially or topologically. A band gap is the range in a solid where no electron state can exist. The band gap of insulators is much larger than in semiconductors. Conductors or metals have a much smaller or nonexistent band gap than semiconductors since the valence and conduction bands overlap. Controlling the band gap allows for the creation of desirable electrical properties.
A rapidly increasing list of graphene production techniques have been developed to enable graphene's use in commercial applications.
Single-layer graphene was first unambiguously produced and identified in 2004, by the group of Andre Geim and Konstantin Novoselov, though they credit Hanns-Peter Boehm and his co-workers for the experimental discovery of graphene in 1962; while it had been explored theoretically by P. R. Wallace in 1947. Boehm et al. introduced the term graphene in 1986.
Two dimensional hexagonal boron nitride is a material of comparable structure to graphene with potential applications in e.g. photonics., fuel cells and as a substrate for two-dimensional heterostructures. 2D h-BN is isostructural to graphene, but where graphene is conductive, 2D h-BN is a wide-gap insulator.
Twistronics is the study of how the angle between layers of two-dimensional materials can change their electrical properties. Materials such as bilayer graphene have been shown to have vastly different electronic behavior, ranging from non-conductive to superconductive, that depends sensitively on the angle between the layers. The term was first introduced by the research group of Efthimios Kaxiras at Harvard University in their theoretical treatment of graphene superlattices.
Artificial lattice is a term encompassing every atomic-scale structures designed and controlled to confine electrons onto a chosen lattice. Research has been done on multiple geometries and one of the most notable being what is called molecular graphene. Molecular graphene is a part of two-dimensional artificial lattices.
References
- ↑ Johnson, Hamish (20 June 2011). "Introducing the 'wrinklon'". Physics World . Retrieved 26 Feb 2014.
- ↑ Meng, Lan; Su, Ying; Geng, Dechao; Yu, Gui; Liu, Yunqi; Dou, Rui-Fen; Nie, Jia-Cai; He, Lin (2013). "Hierarchy of graphene wrinkles induced by thermal strain engineering". Applied Physics Letters. 103 (25): 251610. arXiv: 1306.0171 . Bibcode:2013ApPhL.103y1610M. doi:10.1063/1.4857115. S2CID 119234537.
- ↑ Androulidakis, Charalampos; Koukaras, Emmanuel N.; Sampathkumar, Krishna; Rahova, Jaroslava; Galiotis, Costas; Frank, Otakar (2020). "Hierarchy of nanoscale graphene wrinkles on compliant substrate: Theory and experiment". Extreme Mechanics Letters. 40: 100948. doi:10.1016/j.eml.2020.100948. S2CID 225246967.
| Elementary |
| ||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Composite |
| ||||||||||||||||||||||||
| Quasiparticles | |||||||||||||||||||||||||
| Lists | |||||||||||||||||||||||||
| Related | |||||||||||||||||||||||||
