The Experts below are selected from a list of 297 Experts worldwide ranked by ideXlab platform
Susumu Noda - One of the best experts on this subject based on the ideXlab platform.
-
Tandem photonic-crystal thin films surpassing Lambertian light-trapping limit over broad bandwidth and Angular Range
Applied Physics Letters, 2014Co-Authors: Ardavan Oskooi, Yoshinori Tanaka, Susumu NodaAbstract:Random surface texturing of an optically thick film to increase the path length of scattered light rays, first proposed nearly thirty years ago, has thus far remained the most effective approach for photon absorption over the widest set of conditions. Here, using recent advances in computational electrodynamics, we describe a general strategy for the design of a silicon thin film applicable to photovoltaic cells based on a quasi-resonant approach to light trapping where two partially disordered photonic-crystal slabs, stacked vertically on top of each other, have large absorption that surpasses the Lambertian limit over a broad bandwidth and Angular Range.
-
Tandem Photonic-Crystal Thin Films Surpassing Lambertian Light-Trapping Limit Over Broad Bandwidth and Angular Range
2013Co-Authors: Ardavan Oskooi, Susumu NodaAbstract:The maximum absorption of solar radiation over the broadest Range of frequencies and incident angles using the thinnest material possible has important applications for renewable-energy generation. Complete random texturing of the film surface to increase the path length of light rays, first proposed nearly thirty years ago, has thus far remained the most effective approach for photon absorption over the widest set of conditions. Recent nanostructured designs involving resonant wave effects of photons have explored the possibility of superior performance though as of yet no proposal satisfying the dual requirements of enhanced and robust absorption over a large fraction of the solar spectrum has been made. Here we describe a general strategy for the design of absorbing semiconductor thin films based on a tandem structure where two partially-disordered photonic-crystal slabs, stacked vertically on top of each other, have large absorption that surpasses by a wide margin the Lambertian light-trapping limit over a broad bandwidth and Angular Range for a film with the same thickness as the combined layers. This tandem structure, the photonic analogue of the multi-junction solar cell, has almost double the improvement in the light trapping relative to a single-lattice design with equivalent thickness and is five times more effective than an unpat-terned slab.
Ardavan Oskooi - One of the best experts on this subject based on the ideXlab platform.
-
Tandem photonic-crystal thin films surpassing Lambertian light-trapping limit over broad bandwidth and Angular Range
Applied Physics Letters, 2014Co-Authors: Ardavan Oskooi, Yoshinori Tanaka, Susumu NodaAbstract:Random surface texturing of an optically thick film to increase the path length of scattered light rays, first proposed nearly thirty years ago, has thus far remained the most effective approach for photon absorption over the widest set of conditions. Here, using recent advances in computational electrodynamics, we describe a general strategy for the design of a silicon thin film applicable to photovoltaic cells based on a quasi-resonant approach to light trapping where two partially disordered photonic-crystal slabs, stacked vertically on top of each other, have large absorption that surpasses the Lambertian limit over a broad bandwidth and Angular Range.
-
Tandem Photonic-Crystal Thin Films Surpassing Lambertian Light-Trapping Limit Over Broad Bandwidth and Angular Range
2013Co-Authors: Ardavan Oskooi, Susumu NodaAbstract:The maximum absorption of solar radiation over the broadest Range of frequencies and incident angles using the thinnest material possible has important applications for renewable-energy generation. Complete random texturing of the film surface to increase the path length of light rays, first proposed nearly thirty years ago, has thus far remained the most effective approach for photon absorption over the widest set of conditions. Recent nanostructured designs involving resonant wave effects of photons have explored the possibility of superior performance though as of yet no proposal satisfying the dual requirements of enhanced and robust absorption over a large fraction of the solar spectrum has been made. Here we describe a general strategy for the design of absorbing semiconductor thin films based on a tandem structure where two partially-disordered photonic-crystal slabs, stacked vertically on top of each other, have large absorption that surpasses by a wide margin the Lambertian light-trapping limit over a broad bandwidth and Angular Range for a film with the same thickness as the combined layers. This tandem structure, the photonic analogue of the multi-junction solar cell, has almost double the improvement in the light trapping relative to a single-lattice design with equivalent thickness and is five times more effective than an unpat-terned slab.
Frank H. Read - One of the best experts on this subject based on the ideXlab platform.
-
A study of inelastic electron scattering in He covering the complete Angular Range from to
Journal of Physics B: Atomic Molecular and Optical Physics, 1999Co-Authors: D Cubric, D J L Mercer, J M Channing, G C King, Frank H. ReadAbstract:Differential cross sections for electron impact excitation of the first four excited states of helium have been measured for electron impact energies of 30, 40 and 50 eV. A novel `magnetic angle-changing' technique has been used which allows the full Angular Range from to to be covered for the first time. Serious discrepancies between theory and experiment have been found at angles that were previously inaccessible experimentally.
-
A study of resonance structures in elastic electron scattering from helium, neon, argon, krypton and xenon over the Angular Range from 100 to 180
Journal of Physics B: Atomic Molecular and Optical Physics, 1999Co-Authors: Mariusz Zubek, G C King, Brygida Mielewska, J Channing, Frank H. ReadAbstract:Resonance structures corresponding to the 2sS state in He and the np(n + 1) s(S) states in Ne, Ar, Kr and Xe have been studied in elastic electron scattering over the Angular Range from 100 to 180. A newly developed magnetic angle-changing technique has been used and this has allowed the first observation of these structures at and near to 180. The widths and energies of the resonance states in krypton and xenon have been determined.
Toshiyuki Fujimoto - One of the best experts on this subject based on the ideXlab platform.
-
towards automatic electron tomography for rod shaped specimen
E-journal of Surface Science and Nanotechnology, 2010Co-Authors: Misa Hayashida, Yoshihide Kimura, Toshiyuki FujimotoAbstract:This paper describes a method for automatic acquisition of a high-resolution transmission electron microscope (TEM) tilt series over the full Angular Range from −90° to +90° for TEM tomography. The goniometer controller of a conventional TEM was modified to allow external computer control over specimen position along the three translational and one rotational axis. The TEM parameters, stage motion, and image acquisition were synchronously controlled by home-coded software. The shift in the specimen position with each step of rotation was determined at low magnification by the cross-correlation function and then compensated by moving the stage. The image shift coil and objective lens were only used for fine-tuning. As a result, a tilt series over a full Angular Range was automatically collected at a magnification of around ×200k. The specimen position remained within less than around ±100 nm in the three directions during image collection. [DOI: 10.1380/ejssnt.2010.178]
-
Automatic coarse-alignment for TEM tilt series of rod-shaped specimens collected with a full Angular Range
Micron, 2010Co-Authors: Misa Hayashida, Shin-ya Terauchi, Toshiyuki FujimotoAbstract:Abstract An automatic coarse-alignment method for a tilt series of rod-shaped specimen collected with a full Angular Range (from α = −90° to +90°, α is the tilt angle of the specimen) is presented; this method is based on a cross-correlation method and uses the outline of the specimen shape. Both the rotational angle of the tilt axis and translational value of each image can be detected in the images without the use of markers. This method is performed on the basis of the assumption that the images taken at α = −90° and α = + 90° are symmetric about the tilt axis. In this study, a carbon rod on which gold particles have been deposited is used as a test specimen for the demonstration. This method can be used as an automatic coarse-alignment method prior to the application of a highly accurate alignment method because the alignment procedure can be performed automatically except for the initial setup of some parameters.
Yoshinori Tanaka - One of the best experts on this subject based on the ideXlab platform.
-
Tandem photonic-crystal thin films surpassing Lambertian light-trapping limit over broad bandwidth and Angular Range
Applied Physics Letters, 2014Co-Authors: Ardavan Oskooi, Yoshinori Tanaka, Susumu NodaAbstract:Random surface texturing of an optically thick film to increase the path length of scattered light rays, first proposed nearly thirty years ago, has thus far remained the most effective approach for photon absorption over the widest set of conditions. Here, using recent advances in computational electrodynamics, we describe a general strategy for the design of a silicon thin film applicable to photovoltaic cells based on a quasi-resonant approach to light trapping where two partially disordered photonic-crystal slabs, stacked vertically on top of each other, have large absorption that surpasses the Lambertian limit over a broad bandwidth and Angular Range.
