123 research outputs found

    Approaches to Three-Dimensional Transformation Optical Media Using Quasi-Conformal Coordinate Transformations

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    We introduce an approach to the design of three-dimensional transformation optical (TO) media based on a generalized quasi-conformal mapping approach. The generalized quasi-conformal TO (QCTO) approach enables the design of media that can, in principle, be broadband and low-loss, while controlling the propagation of waves with arbitrary angles of incidence and polarization. We illustrate the method in the design of a three-dimensional "carpet" ground plane cloak and of a flattened Luneburg lens. Ray-trace studies provide a confirmation of the performance of the QCTO media, while also revealing the limited performance of index-only versions of these devices

    The Ultimate Struggles of a classroom

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    Abstract: In a time where classrooms need more development as a whole to be more sustainable for kids that might have learning disabilities, We will look into universal design techniques that teachers could use to help children succeed in their environment. Having some sort of adaptability in the classroom is important for all students. By changing the ways we teach some tools teachers can use will be more comforting for the student with a learning disability to learn at quicker and faster paces. Design and having structure is very effective to student learning efficiency. Looking at new ways to innovate a classroom or a school could be beneficial. Also having certain seating arrangements for kids that might have social anxiety or a learning disabilities could help a child with needs in an environment that they might have to get used to. Having these different styles of teaching where students are more interactive together in a comfortable classroom setting is effective in how a child with learning disabilities processes and learns information

    Quantum Electric Circuits Analogous to Ballistic Conductors

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    The conductance steps in a constricted two-dimensional electron gas and the minimum conductivity in graphene are related to a new uncertainty relation between electric charge and conductance in a quantized electric circuit that mimics the electric transport in mesoscopic systems. This uncertainty relation makes specific use of the discreteness of electric charge. Quantum electric circuits analogous to both constricted two-dimensional electron gas and graphene are introduced. In the latter case a new insight into the origin of minimum conductivity is obtained.Comment: 14 page

    Collimating lenses from non-Euclidean transformation optics

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    Based on the non-Euclidean transformation optics, we design a thin metamaterial lens that can achieve wide-beam radiation by embedding a simple source (a point source in three-dimensional case or a line current source in two-dimensional case). The scheme is performed on a layer-by-layer geometry to convert curved surfaces in virtual space to flat sheets, which pile up and form the entire lens in physical space. Compared to previous designs, the lens has no extreme material parameters. Simulation results confirm its functionality.Comment: 12 pages, 6 figure

    Perfect imaging with positive refraction in three dimensions

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    Maxwell's fish eye has been known to be a perfect lens within the validity range of ray optics since 1854. Solving Maxwell's equations we show that the fish-eye lens in three dimensions has unlimited resolution for electromagnetic waves

    Perfect imaging with geodesic waveguides

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    Transformation optics is used to prove that a spherical waveguide filled with an isotropic material with radial refractive index n=1/r has radial polarized modes (i.e. the electric field has only radial component) with the same perfect focusing properties as the Maxwell Fish-Eye lens. The approximate version of that device using a thin waveguide with a homogenous core paves the way to experimentally prove perfect imaging in the Maxwell Fish Eye lens

    Snell's Law from an Elementary Particle Viewpoint

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    Snell's law of light deflection between media with different indices of refraction is usually discussed in terms of the Maxwell electromagnetic wave theory. Snell's law may also be derived from a photon beam theory of light rays. This latter particle physics view is by far the most simple one for understanding the laws of refraction.Comment: ReVTeX Format 2 *.eps figure

    Perfect imaging: they don't do it with mirrors

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    Imaging with a spherical mirror in empty space is compared with the case when the mirror is filled with the medium of Maxwell's fish eye. Exact time-dependent solutions of Maxwell's equations show that perfect imaging is not achievable with an electrical ideal mirror on its own, but with Maxwell's fish eye in the regime when it implements a curved geometry for full electromagnetic waves

    Absolute instruments and perfect imaging in geometrical optics

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    We investigate imaging by spherically symmetric absolute instruments that provide perfect imaging in the sense of geometrical optics. We derive a number of properties of such devices, present a general method for designing them and use this method to propose several new absolute instruments, in particular a lens providing a stigmatic image of an optically homogeneous region and having a moderate refractive index range.Comment: 20 pages, 9 image
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