Construction Techniques
The idea that man can create materials which have properties not found in nature is profound, however in reality this is a relatively simple process. One designs a unit cell or meta-atom and then binds these meta-atoms into a structure creating a metamaterial [1]. Such a metamaterial can have optical properties which can be adapted to a certain requirement. To make a Negative index metamaterial, NIM, the requirement is that the refractive index, n, should be negative. By building certain shapes of meta-atom the permeability, µ, and permittivity, ԑ, of the metamaterial can in theory be chosen. From a construction point of view there are two branches of metamaterials which are 2D and 3D NIMs, and the construction techniques differ between the two branches. 2D NIMs are metamaterials constructed with just one layer of meta-atoms, whereas 3D NIMs are constructed with many layers placed above one another.
When making a NIM there are some considerations which need to be taken into account [2]. Firstly the size of the meta-atom must be much smaller than the wavelength of the radiation that is to incident on it. Secondly the losses from the material the NIM is fabricated from also plays an important role, NIMs made using low loss materials such as gold and silver. Thirdly Homogeneity is required to create a NIM which the radiation will interact with uniformly.
The Electron beam lithography process utilises a beam of electrons to create periodic voids on the surface of a resist which will have a negative refractive index at certain wavelengths. The width of electron beam can be adjusted to have a width on the nano-scale, which is necessary for the incident electromagnetic radiation to interact with the metama...
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...Liu, Z. Yu, N. Fang, Y.R. Shen, A.M. Bratkovsky,W. Tong, C. Sun, X. Zhang, S.-Y.Wang, R.S. Williams, Optical metamaterials at near and mid-IR range fabricated by nanoimprint lithography, Appl. Phys. A 87 (2007) 147.
[8] Na Liu, Hongcang Guo, Liwei Fu, Stefan Kaiser, Heinz Schweizer & Harald Giessen, Three-dimensional photonic metamaterials at optical frequencies, Nature Materials 7, 31 - 37 (2008)
[9] S. Maruo, O. Nakamura, S. Kawata, Three-dimensional microfabrication with two-photon-absorbed photopolymerization, Opt. Lett. 22 (1997) 132.
[10] Wei Zhao and Xiaopeng Zhao Fabrication and characterization of metamaterials at optical frequencies, Opt. Materials 32, 422-426 (2010)
[11] Yi-Jun Jen, Akhlesh Lakhtakia, Ching-Wei Yu, and Chin-Te Lin, "Vapor-deposited thin films with negative real refractive index in the visible regime," Opt. Express 17, 7784-7789 (2009)
The small size ranging from 0.1 to 10 micrometres of nanobots make it difficult to be constructed. The process of working atom by atom and molecule by molecule is monotonous work and the miniaturization of synthetic mechanisms to a nanoscale will only be achievable with the advancement of research in metallurgy.
Throughout the past century, investigations of quantum and particle physics phenomena have proven to show the most significant concepts and ideas in the physical and sub-atomic world. However, the discoveries yet to be made are endless. One of the most fascinating concepts in the sub-atomic universe is the idea of spintronics. Spintronics is the quantum study of the independent angular momentum (not to be confused with the orbital angular momentum of the electron) of a particle, typically that of an electron (Introduction). An electron is a fundamental particle, with a negative charge, and is independently studied in the process of spintronic devices. The spin angular momentum of electrons is ±½ћ. Devices that use the properties
Building a yurt might sound complicated, but there are several techniques and tools that will make the process easier for everyone. As was previously stated, the first step to build a yurt is deciding where to place it. The area should be analyzed. The moisture and sun exposure of the region should be analyzed as well. The team decided to locate the yurt in Costa Rica because of the neutral weather and the sunny and hot days. Also, in Costa Rica will be easier to get through the building codes rather than in the United States. However, the first step to build it consists of making a list of all the tools, materials, workers, and equipment needed in order to build the yurt.
Warner, Jamie H., Franziska Schaffel, Mark Rummeli, and Alicja Bachmatiuk. Graphene: Fundamentals and Emergent Applications. Burlington, 17 Nov. 2012. Print. 21 Feb. 2014. Hyperlink
19. Novoselov, Kostya S., et al. "Electric field effect in atomically thin carbon films." science 306.5696 (2004): 666-669.
2. Lithography: Lithography in the MEMS context is typically the transfer of a pattern to a photosensitive material by selective exposure to a radiation source such as light. In lithography for micromachining, the photosensitive material used is typically a photoresist. When resist is exposed to a radiation source of a specific a wavelength, the chemical resistance of the resist to developer solution changes.
M2 Construction is well known for maintaining the highest standards in regarding of Quality Performance. In order to achieve a completed project that meets the owner 's quality expectations, we require that all parties to a project must acquire an understanding of those expectations, incorporate them into the contract price, and commit in good faith to carry them out.
Serway, Raymond A, and Robert J Beichner. Physics: For Scientists and Engineers. United States of
American Institute of Physics. Vol. 1051 Issue 1 (2008). Academic Search Premier.> 224. http://login.ezproxy1.lib.asu.edu/login?url=http://search.ebscohost.com.ezproxy1.lib.asu.edu/login.aspx?direct=true&db=aph&AN=34874307&site=ehost-live.
Brooke (1997), explains Estimation as the technical procedure of anticipating the value of the project. Building construction estimation is the process of acquiring the construction value for the whole project before the project starts. Thus, construction attaining process depends hugely on financial management to sustain workability and smooth operations. The delay in construction is a global issue which is due to improper preparation of estimates and lack of drawings (Ajanlekoko, 1987). In accordance to Gkritza (2008), the source of delay in a project are identified to be in the initial stages, like bad quantification, errors in design and ground conditions. Thus, the purpose of a proper estimate is to foretell the cost needed to finish the
Alford, Terry L., L. C. Feldman, and James W. Mayer. Fundamentals of Nanoscale Film Analysis. New York: Springer, 2007. Print.
T10.1b shows positive charges. In both cases the magnetic force is upward, just as the magnetic force on a conductor is the same whether the moving charges are positive or negative. In either case a moving charge is driven toward the upper edge of the strip by the magnetic force Fz = |q|vdB. If the charge carriers are electrons, an excess negative charge accumulates at the upper edge of the strip, leaving an excess positive charge at its lower edge. This accumulation continues until the resulting transverse electrostatic field E becomes large enough to cause a force (magnitude |q|E) that is equal and opposite to the magnetic force (magnitude |q|vd B). After that, there is no longer any net transverse force to deflect the moving charges. This electric field causes a transverse potential difference between opposite edges of the strip, called the Hall voltage or the Hall emf. The polarity depends on whether the moving charges are positive or negative. Experiments show that for metals the upper edge of the strip in Fig. T10.1a does become negatively charged, showing that the charge carriers in a metal are indeed negative
Grundmann, Marius. Physics of Semiconductors: An Introduction Including Devices and Nanophysics. New York: Springer, 2006. Print.
As a graduate student, I will undertake research and coursework in Electrical Engineering to enhance my competencies in this field. I intend to complete my master's degree in order to pursue my doctorate. The research that I am most interested in pursuing at Northeastern University surrounds the optical properties of MEMS devices, and the development of substrate-based fast electro-optical interfaces. My interest in this area stems from my undergraduate study in MEMs development for tri-axial accelerometers.
Davisson and Germer found that by varying the applied voltage to the electron gun, the maximum intensity of electrons diffracted by the atomic surface was found at different angles. The highest intensity was found to be at an angle θ = 50° with a voltage of 54 V, giving the electrons a kinetic energy of 54 eV.