The Experts below are selected from a list of 294 Experts worldwide ranked by ideXlab platform
Y Low - One of the best experts on this subject based on the ideXlab platform.
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wavelength selective 1 spl times k switches using free space optics and mems micromirrors theory design and implementation
Journal of Lightwave Technology, 2005Co-Authors: Dan M. Marom, Chien-shing Pai, Daniel O. López, Maria Elina Simon, Dennis S Greywall, Nagesh R Basavanhally, David T. Neilson, Vladimir A Aksyuk, D. Lopez, Flavio Pardo, Y LowAbstract:The design and performance of several generations of wavelength-selective 1/spl times/K switches are reviewed. These optical subsystems combine the functionality of a demultiplexer, per-wavelength switch, and multiplexer in a single, low-loss unit. Free-space optics is utilized for spatially separating the constituent wavelength division multiplexing (WDM) Channels as well as for space-division switching from an input optical fiber to one of K output fibers (1/spl times/K functionality) on a Channel-by-Channel Basis using a microelectromechanical system (MEMS) micromirror array. The switches are designed to provide wide and flat passbands for minimal signal distortion. They can also provide spectral equalization and Channel blocking functionality, making them well suited for use in transparent WDM optical mesh networks.
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Wavelength-selective 1/spl times/K switches using free-space optics and MEMS micromirrors: theory, design, and implementation
Journal of Lightwave Technology, 2005Co-Authors: Dan M. Marom, Chien-shing Pai, Daniel O. López, Maria Elina Simon, Dennis S Greywall, Nagesh R Basavanhally, David T. Neilson, Vladimir A Aksyuk, Flavio Pardo, Y LowAbstract:The design and performance of several generations of wavelength-selective 1/spl times/K switches are reviewed. These optical subsystems combine the functionality of a demultiplexer, per-wavelength switch, and multiplexer in a single, low-loss unit. Free-space optics is utilized for spatially separating the constituent wavelength division multiplexing (WDM) Channels as well as for space-division switching from an input optical fiber to one of K output fibers (1/spl times/K functionality) on a Channel-by-Channel Basis using a microelectromechanical system (MEMS) micromirror array. The switches are designed to provide wide and flat passbands for minimal signal distortion. They can also provide spectral equalization and Channel blocking functionality, making them well suited for use in transparent WDM optical mesh networks.
Dan M. Marom - One of the best experts on this subject based on the ideXlab platform.
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wavelength selective 1 spl times k switches using free space optics and mems micromirrors theory design and implementation
Journal of Lightwave Technology, 2005Co-Authors: Dan M. Marom, Chien-shing Pai, Daniel O. López, Maria Elina Simon, Dennis S Greywall, Nagesh R Basavanhally, David T. Neilson, Vladimir A Aksyuk, D. Lopez, Flavio Pardo, Y LowAbstract:The design and performance of several generations of wavelength-selective 1/spl times/K switches are reviewed. These optical subsystems combine the functionality of a demultiplexer, per-wavelength switch, and multiplexer in a single, low-loss unit. Free-space optics is utilized for spatially separating the constituent wavelength division multiplexing (WDM) Channels as well as for space-division switching from an input optical fiber to one of K output fibers (1/spl times/K functionality) on a Channel-by-Channel Basis using a microelectromechanical system (MEMS) micromirror array. The switches are designed to provide wide and flat passbands for minimal signal distortion. They can also provide spectral equalization and Channel blocking functionality, making them well suited for use in transparent WDM optical mesh networks.
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Wavelength-selective 1/spl times/K switches using free-space optics and MEMS micromirrors: theory, design, and implementation
Journal of Lightwave Technology, 2005Co-Authors: Dan M. Marom, Chien-shing Pai, Daniel O. López, Maria Elina Simon, Dennis S Greywall, Nagesh R Basavanhally, David T. Neilson, Vladimir A Aksyuk, Flavio Pardo, Y LowAbstract:The design and performance of several generations of wavelength-selective 1/spl times/K switches are reviewed. These optical subsystems combine the functionality of a demultiplexer, per-wavelength switch, and multiplexer in a single, low-loss unit. Free-space optics is utilized for spatially separating the constituent wavelength division multiplexing (WDM) Channels as well as for space-division switching from an input optical fiber to one of K output fibers (1/spl times/K functionality) on a Channel-by-Channel Basis using a microelectromechanical system (MEMS) micromirror array. The switches are designed to provide wide and flat passbands for minimal signal distortion. They can also provide spectral equalization and Channel blocking functionality, making them well suited for use in transparent WDM optical mesh networks.
Gerrit C. Groenenboom - One of the best experts on this subject based on the ideXlab platform.
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Cold and ultracold NH--NH collisions: The field-free case
The Journal of chemical physics, 2011Co-Authors: Liesbeth M. C. Janssen, A. Van Der Avoird, Jeremy M. Hutson, Piotr S. Żuchowski, Gerrit C. GroenenboomAbstract:We present elastic and inelastic spin-changing cross sections for cold and ultracold NH($X\,^3\Sigma^-$) + NH($X\,^3\Sigma^-$) collisions, obtained from full quantum scattering calculations on an accurate \textit{ab initio} quintet potential-energy surface. Although we consider only collisions in zero field, we focus on the cross sections relevant for magnetic trapping experiments. It is shown that evaporative cooling of both fermionic $^{14}$NH and bosonic $^{15}$NH is likely to be successful for hyperfine states that allow for s-wave collisions. The calculated cross sections are very sensitive to the details of the interaction potential, due to the presence of (quasi-)bound state resonances. The remaining inaccuracy of the \textit{ab initio} potential-energy surface therefore gives rise to an uncertainty in the numerical cross-section values. However, based on a sampling of the uncertainty range of the \textit{ab initio} calculations, we conclude that the exact potential is likely to be such that the elastic-to-inelastic cross-section ratio is sufficiently large to achieve efficient evaporative cooling. This likelihood is only weakly dependent on the size of the Channel Basis set used in the scattering calculations.
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Cold and ultracold nh-nh collisions in magnetic fields
Physical Review A, 2011Co-Authors: Liesbeth M. C. Janssen, Piotr S. Zuchowski, A. Van Der Avoird, Gerrit C. Groenenboom, Jeremy M. HutsonAbstract:Elastic and spin-changing inelastic collision cross sections are presented for cold and ultracold magnetically trapped NH. The cross sections are obtained from coupled-Channel scattering calculations as a function of energy and magnetic field. We specifically investigate the influence of the intramolecular spin-spin, spin-rotation, and intermolecular magnetic dipole coupling on the collision dynamics. It is shown that $^{15}\mathrm{N}$H is a very suitable candidate for evaporative cooling experiments. The dominant trap-loss mechanism in the ultracold regime originates from the intermolecular dipolar coupling term. At higher energies and fields, intramolecular spin-spin coupling becomes increasingly important. Our qualitative results and conclusions are fairly independent of the exact form of the potential and of the size of the Channel Basis set.
Jeremy M. Hutson - One of the best experts on this subject based on the ideXlab platform.
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Cold and ultracold NH--NH collisions: The field-free case
The Journal of chemical physics, 2011Co-Authors: Liesbeth M. C. Janssen, A. Van Der Avoird, Jeremy M. Hutson, Piotr S. Żuchowski, Gerrit C. GroenenboomAbstract:We present elastic and inelastic spin-changing cross sections for cold and ultracold NH($X\,^3\Sigma^-$) + NH($X\,^3\Sigma^-$) collisions, obtained from full quantum scattering calculations on an accurate \textit{ab initio} quintet potential-energy surface. Although we consider only collisions in zero field, we focus on the cross sections relevant for magnetic trapping experiments. It is shown that evaporative cooling of both fermionic $^{14}$NH and bosonic $^{15}$NH is likely to be successful for hyperfine states that allow for s-wave collisions. The calculated cross sections are very sensitive to the details of the interaction potential, due to the presence of (quasi-)bound state resonances. The remaining inaccuracy of the \textit{ab initio} potential-energy surface therefore gives rise to an uncertainty in the numerical cross-section values. However, based on a sampling of the uncertainty range of the \textit{ab initio} calculations, we conclude that the exact potential is likely to be such that the elastic-to-inelastic cross-section ratio is sufficiently large to achieve efficient evaporative cooling. This likelihood is only weakly dependent on the size of the Channel Basis set used in the scattering calculations.
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Cold and ultracold nh-nh collisions in magnetic fields
Physical Review A, 2011Co-Authors: Liesbeth M. C. Janssen, Piotr S. Zuchowski, A. Van Der Avoird, Gerrit C. Groenenboom, Jeremy M. HutsonAbstract:Elastic and spin-changing inelastic collision cross sections are presented for cold and ultracold magnetically trapped NH. The cross sections are obtained from coupled-Channel scattering calculations as a function of energy and magnetic field. We specifically investigate the influence of the intramolecular spin-spin, spin-rotation, and intermolecular magnetic dipole coupling on the collision dynamics. It is shown that $^{15}\mathrm{N}$H is a very suitable candidate for evaporative cooling experiments. The dominant trap-loss mechanism in the ultracold regime originates from the intermolecular dipolar coupling term. At higher energies and fields, intramolecular spin-spin coupling becomes increasingly important. Our qualitative results and conclusions are fairly independent of the exact form of the potential and of the size of the Channel Basis set.
Liesbeth M. C. Janssen - One of the best experts on this subject based on the ideXlab platform.
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Cold and ultracold NH--NH collisions: The field-free case
The Journal of chemical physics, 2011Co-Authors: Liesbeth M. C. Janssen, A. Van Der Avoird, Jeremy M. Hutson, Piotr S. Żuchowski, Gerrit C. GroenenboomAbstract:We present elastic and inelastic spin-changing cross sections for cold and ultracold NH($X\,^3\Sigma^-$) + NH($X\,^3\Sigma^-$) collisions, obtained from full quantum scattering calculations on an accurate \textit{ab initio} quintet potential-energy surface. Although we consider only collisions in zero field, we focus on the cross sections relevant for magnetic trapping experiments. It is shown that evaporative cooling of both fermionic $^{14}$NH and bosonic $^{15}$NH is likely to be successful for hyperfine states that allow for s-wave collisions. The calculated cross sections are very sensitive to the details of the interaction potential, due to the presence of (quasi-)bound state resonances. The remaining inaccuracy of the \textit{ab initio} potential-energy surface therefore gives rise to an uncertainty in the numerical cross-section values. However, based on a sampling of the uncertainty range of the \textit{ab initio} calculations, we conclude that the exact potential is likely to be such that the elastic-to-inelastic cross-section ratio is sufficiently large to achieve efficient evaporative cooling. This likelihood is only weakly dependent on the size of the Channel Basis set used in the scattering calculations.
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Cold and ultracold nh-nh collisions in magnetic fields
Physical Review A, 2011Co-Authors: Liesbeth M. C. Janssen, Piotr S. Zuchowski, A. Van Der Avoird, Gerrit C. Groenenboom, Jeremy M. HutsonAbstract:Elastic and spin-changing inelastic collision cross sections are presented for cold and ultracold magnetically trapped NH. The cross sections are obtained from coupled-Channel scattering calculations as a function of energy and magnetic field. We specifically investigate the influence of the intramolecular spin-spin, spin-rotation, and intermolecular magnetic dipole coupling on the collision dynamics. It is shown that $^{15}\mathrm{N}$H is a very suitable candidate for evaporative cooling experiments. The dominant trap-loss mechanism in the ultracold regime originates from the intermolecular dipolar coupling term. At higher energies and fields, intramolecular spin-spin coupling becomes increasingly important. Our qualitative results and conclusions are fairly independent of the exact form of the potential and of the size of the Channel Basis set.