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Mihail M. Sigalas - One of the best experts on this subject based on the ideXlab platform.
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Photonic Band gaps in colloidal systems
Physical Review B, 1998Co-Authors: Rana Biswas, Mihail M. Sigalas, Ganapathi Subramanian SubramaniaAbstract:Classes of colloidal dielectric systems are found with full three-dimensional Photonic Band gaps, using Photonic Band-structure calculations. The fcc structure composed from either high dielectric spheres or low dielectric spheres has three-dimensional Band gaps and lower-frequency pseudogaps. The AB2 structure has a higher-frequency pseudogap. {copyright} {ital 1998} {ital The American Physical Society}
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Slot antennas on Photonic Band gap crystals
IEEE Transactions on Antennas and Propagation, 1997Co-Authors: Wai Y. Leung, Rana Biswas, Mihail M. Sigalas, Shi-di Cheng, J. S. Mccalmont, G. TuttleAbstract:The radiation patterns of a slot antenna placed on a Photonic Band gap crystal have been measured. We used a layer-by-layer Photonic Band gap crystal having a three-dimensional stop Band between 12 and 15 GHz. The slot antenna radiation depends sensitively on the relative position and orientation of the slot in the surface unit cell of the Photonic crystal. We have found configurations of the slot antenna with an increase of radiated power by 2-3 dB. The Photonic Band gap crystal can considerably improve the performance of a simple slot antenna.
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Micromachined millimeter‐wave Photonic Band‐gap crystals
Applied Physics Letters, 1994Co-Authors: Ekmel Ozbay, E. Michel, G. Tuttle, Rana Biswas, Mihail M. SigalasAbstract:We have developed a new technique for fabricating three‐dimensional Photonic Band‐gap crystals. Our method utilizes an orderly stacking of micromachined (110) silicon wafers to build the periodic structure. A structure with a full three‐dimensional Photonic Band gap centered near 100 GHz was measured, with experimental results in good agreement with theoretical predictions. This basic approach described should be extendable to build structures with Photonic Band‐gap frequencies ranging from 30 GHz to 3 THz.
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micromachined millimeter wave Photonic Band gap crystals
Applied Physics Letters, 1994Co-Authors: Ekmel Ozbay, E. Michel, G. Tuttle, Rana Biswas, Mihail M. SigalasAbstract:We have developed a new technique for fabricating three‐dimensional Photonic Band‐gap crystals. Our method utilizes an orderly stacking of micromachined (110) silicon wafers to build the periodic structure. A structure with a full three‐dimensional Photonic Band gap centered near 100 GHz was measured, with experimental results in good agreement with theoretical predictions. This basic approach described should be extendable to build structures with Photonic Band‐gap frequencies ranging from 30 GHz to 3 THz.
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New structures and algorithms for Photonic Band gaps
Physica A: Statistical Mechanics and its Applications, 1994Co-Authors: Che Ting Chan, Mihail M. Sigalas, S. Datta, Costas M. SoukoulisAbstract:A new class of structure is found to possess Photonic Band gaps, and it contains most of the previously known Photonic Band gap structures as its subsets. We will also present some results concerning the EM wave eigenstates of structures with structural dffects and the transmission characteristics of periodic materials with one component being dispersive and absorbing.
Ekmel Ozbay - One of the best experts on this subject based on the ideXlab platform.
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Photonic Band gaps with layer‐by‐layer double‐etched structures
Journal of Applied Physics, 1996Co-Authors: Rana Biswas, Ekmel OzbayAbstract:Periodic layer‐by‐layer dielectric structures with full three‐dimensional Photonic Band gaps have been designed and fabricated. In contrast to previous layer‐by‐layer structures the rods in each successive layer are at an angle of 70.5° to each other, achieved by etching both sides of a silicon wafer. Photonic Band‐structure calculations are utilized to optimize the Photonic Band gap by varying the structural geometry. The structure has been fabricated by double etching Si wafers producing millimeter wave Photonic Band gaps between 300 and 500 GHz, in excellent agreement with Band calculations. Overetching this structure produces a multiply connected geometry and increases both the size and frequency of the Photonic Band gap, in very good agreement with experimental measurements. This new robust double‐etched structure doubles the frequency possible from a single Si wafer, and can be scaled to produced Band gaps at higher frequencies.
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Optimized dipole antennas on Photonic Band gap crystals
Applied Physics Letters, 1995Co-Authors: Shi-di Cheng, Ekmel Ozbay, Rana Biswas, S. Mccalmont, G. TuttleAbstract:Photonic Band gap crystals have been used as a perfectly reflecting substrate for planar dipole antennas in the 12–15 GHz regime. The position, orientation, and driving frequency of the dipole antenna on the Photonic Band gap crystal surface, have been optimized for antenna performance and directionality. Virtually no radiated power is lost to the Photonic crystal resulting in gains and radiation efficiencies larger than antennas on other conventional dielectric substrates.
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Micromachined millimeter‐wave Photonic Band‐gap crystals
Applied Physics Letters, 1994Co-Authors: Ekmel Ozbay, E. Michel, G. Tuttle, Rana Biswas, Mihail M. SigalasAbstract:We have developed a new technique for fabricating three‐dimensional Photonic Band‐gap crystals. Our method utilizes an orderly stacking of micromachined (110) silicon wafers to build the periodic structure. A structure with a full three‐dimensional Photonic Band gap centered near 100 GHz was measured, with experimental results in good agreement with theoretical predictions. This basic approach described should be extendable to build structures with Photonic Band‐gap frequencies ranging from 30 GHz to 3 THz.
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micromachined millimeter wave Photonic Band gap crystals
Applied Physics Letters, 1994Co-Authors: Ekmel Ozbay, E. Michel, G. Tuttle, Rana Biswas, Mihail M. SigalasAbstract:We have developed a new technique for fabricating three‐dimensional Photonic Band‐gap crystals. Our method utilizes an orderly stacking of micromachined (110) silicon wafers to build the periodic structure. A structure with a full three‐dimensional Photonic Band gap centered near 100 GHz was measured, with experimental results in good agreement with theoretical predictions. This basic approach described should be extendable to build structures with Photonic Band‐gap frequencies ranging from 30 GHz to 3 THz.
Rana Biswas - One of the best experts on this subject based on the ideXlab platform.
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Photonic Band gaps in colloidal systems
Physical Review B, 1998Co-Authors: Rana Biswas, Mihail M. Sigalas, Ganapathi Subramanian SubramaniaAbstract:Classes of colloidal dielectric systems are found with full three-dimensional Photonic Band gaps, using Photonic Band-structure calculations. The fcc structure composed from either high dielectric spheres or low dielectric spheres has three-dimensional Band gaps and lower-frequency pseudogaps. The AB2 structure has a higher-frequency pseudogap. {copyright} {ital 1998} {ital The American Physical Society}
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Slot antennas on Photonic Band gap crystals
IEEE Transactions on Antennas and Propagation, 1997Co-Authors: Wai Y. Leung, Rana Biswas, Mihail M. Sigalas, Shi-di Cheng, J. S. Mccalmont, G. TuttleAbstract:The radiation patterns of a slot antenna placed on a Photonic Band gap crystal have been measured. We used a layer-by-layer Photonic Band gap crystal having a three-dimensional stop Band between 12 and 15 GHz. The slot antenna radiation depends sensitively on the relative position and orientation of the slot in the surface unit cell of the Photonic crystal. We have found configurations of the slot antenna with an increase of radiated power by 2-3 dB. The Photonic Band gap crystal can considerably improve the performance of a simple slot antenna.
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Photonic Band gaps with layer‐by‐layer double‐etched structures
Journal of Applied Physics, 1996Co-Authors: Rana Biswas, Ekmel OzbayAbstract:Periodic layer‐by‐layer dielectric structures with full three‐dimensional Photonic Band gaps have been designed and fabricated. In contrast to previous layer‐by‐layer structures the rods in each successive layer are at an angle of 70.5° to each other, achieved by etching both sides of a silicon wafer. Photonic Band‐structure calculations are utilized to optimize the Photonic Band gap by varying the structural geometry. The structure has been fabricated by double etching Si wafers producing millimeter wave Photonic Band gaps between 300 and 500 GHz, in excellent agreement with Band calculations. Overetching this structure produces a multiply connected geometry and increases both the size and frequency of the Photonic Band gap, in very good agreement with experimental measurements. This new robust double‐etched structure doubles the frequency possible from a single Si wafer, and can be scaled to produced Band gaps at higher frequencies.
-
Optimized dipole antennas on Photonic Band gap crystals
Applied Physics Letters, 1995Co-Authors: Shi-di Cheng, Ekmel Ozbay, Rana Biswas, S. Mccalmont, G. TuttleAbstract:Photonic Band gap crystals have been used as a perfectly reflecting substrate for planar dipole antennas in the 12–15 GHz regime. The position, orientation, and driving frequency of the dipole antenna on the Photonic Band gap crystal surface, have been optimized for antenna performance and directionality. Virtually no radiated power is lost to the Photonic crystal resulting in gains and radiation efficiencies larger than antennas on other conventional dielectric substrates.
-
Micromachined millimeter‐wave Photonic Band‐gap crystals
Applied Physics Letters, 1994Co-Authors: Ekmel Ozbay, E. Michel, G. Tuttle, Rana Biswas, Mihail M. SigalasAbstract:We have developed a new technique for fabricating three‐dimensional Photonic Band‐gap crystals. Our method utilizes an orderly stacking of micromachined (110) silicon wafers to build the periodic structure. A structure with a full three‐dimensional Photonic Band gap centered near 100 GHz was measured, with experimental results in good agreement with theoretical predictions. This basic approach described should be extendable to build structures with Photonic Band‐gap frequencies ranging from 30 GHz to 3 THz.
Emmanuel Centeno - One of the best experts on this subject based on the ideXlab platform.
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Superlattice for Photonic Band gap opening in monolayers of dielectric spheres
Optics Express, 2006Co-Authors: Kevin Vynck, David Cassagne, Emmanuel CentenoAbstract:Dielectric spheres synthesized for the fabrication of self-organized Photonic crystals such as opals offer large opportunities for the design of novel nanoPhotonic devices. In this paper, we show that a hexagonal superlattice monolayer of dielectric spheres exhibits an even Photonic Band gap below the light cone for refractive indices higher than 1.93. The use of spheres with refractive index 2.9 and diameter 0.33 μm tunes the Photonic Band gap to the telecommunications range (λ=1.55 μm). As a practical example for the use of such a Photonic Band gap, we demonstrate the possibility of waveguiding light linearly through the monolayer.
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Superlattice for Photonic Band gap opening in monolayers of dielectric spheres
Optics Express, 2006Co-Authors: Kevin Vynck, David Cassagne, Emmanuel CentenoAbstract:Dielectric spheres synthesized for the fabrication of self-organized Photonic crystals such as opals offer large opportunities for the design of novel nanoPhotonic devices. In this paper, we show that a hexagonal superlattice monolayer of dielectric spheres exhibits an even Photonic Band gap below the light cone for refractive indices higher than 1.93. The use of spheres with refractive index 2.9 and diameter 0.33 mu m tunes the Photonic Band gap to the telecommunications range (lambda= 1.55 mu m). As a practical example for the use of such a Photonic Band gap, we demonstrate the possibility of waveguiding light linearly through the monolayer. (c) 2006 Optical Society of America.
E. Michel - One of the best experts on this subject based on the ideXlab platform.
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Micromachined millimeter‐wave Photonic Band‐gap crystals
Applied Physics Letters, 1994Co-Authors: Ekmel Ozbay, E. Michel, G. Tuttle, Rana Biswas, Mihail M. SigalasAbstract:We have developed a new technique for fabricating three‐dimensional Photonic Band‐gap crystals. Our method utilizes an orderly stacking of micromachined (110) silicon wafers to build the periodic structure. A structure with a full three‐dimensional Photonic Band gap centered near 100 GHz was measured, with experimental results in good agreement with theoretical predictions. This basic approach described should be extendable to build structures with Photonic Band‐gap frequencies ranging from 30 GHz to 3 THz.
-
micromachined millimeter wave Photonic Band gap crystals
Applied Physics Letters, 1994Co-Authors: Ekmel Ozbay, E. Michel, G. Tuttle, Rana Biswas, Mihail M. SigalasAbstract:We have developed a new technique for fabricating three‐dimensional Photonic Band‐gap crystals. Our method utilizes an orderly stacking of micromachined (110) silicon wafers to build the periodic structure. A structure with a full three‐dimensional Photonic Band gap centered near 100 GHz was measured, with experimental results in good agreement with theoretical predictions. This basic approach described should be extendable to build structures with Photonic Band‐gap frequencies ranging from 30 GHz to 3 THz.