The Experts below are selected from a list of 64791 Experts worldwide ranked by ideXlab platform

Stefan Knirck - One of the best experts on this subject based on the ideXlab platform.

T Inada - One of the best experts on this subject based on the ideXlab platform.

Emmanuel Guillot - One of the best experts on this subject based on the ideXlab platform.

  • 5 5 w continuous wave tem 00 mode nd yag solar laser by a light guide 2v shaped pump cavity
    Applied Physics B, 2015
    Co-Authors: Joana Almeida, Dawei Liang, Claudia R Vistas, R Bouadjemine, Emmanuel Guillot
    Abstract:

    A significant progress in TEM00-mode solar laser power and efficiency with heliostat–parabolic Mirror System is reported here. A double-stage light-guide/2V-shaped pump cavity is used to efficiently couple and redistribute the concentrated pump light from a 2-m-diameter parabolic Mirror to a 4-mm-diameter, 30-mm-length, 1.1 at.% Nd:YAG single-crystal rod. The light guide with large rectangular cross section enables a stable uniform pumping profile along the laser rod, resulting also in an enhanced tracking error compensation capacity. 5.5 W cw TEM00-mode solar laser power was measured at the output of a thermally near unstable asymmetric resonator. 150 and 157 % improvement in TEM00-mode solar laser collection efficiency and slope efficiency were obtained, respectively.

  • 56 w cw nd yag solar laser by a heliostat parabolic Mirror System
    European Quantum Electronics Conference, 2015
    Co-Authors: Joana Almeida, Dawei Liang, Claudia R Vistas, Emmanuel Guillot
    Abstract:

    Solar-pumped lasers are natural candidates for applications where sunlight is plentiful and few other energy sources are available. Since the first report of “A sun-pumped cw one-watt laser” in 1966 [1], optical and laser material advances have continued to improve solar laser performance. Parabolic Mirrors have long been explored to achieve tight focusing of incoming solar radiation. However, their use for solar laser researches has been neglected in recent years due to the increased interests in large-size Fresnel lenses. Fresnel lens is cost-effective, but it causes the dispersion of the solar radiation along its focal zone, hampering the efficient light concentration to the laser rod. It is therefore valuable for us to carry out the solar laser research with parabolic Mirrors. A new progress in both solar laser collection efficiency and slope efficiency with heliostat - parabolic Mirror System is reported here.

  • highly efficient end side pumped nd yag solar laser by a heliostat parabolic Mirror System
    Applied Optics, 2015
    Co-Authors: Joana Almeida, Dawei Liang, Claudia R Vistas, Emmanuel Guillot
    Abstract:

    We report a large improvement in the collection and slope efficiency of an Nd:YAG solar laser pumped by a heliostat–parabolic Mirror System. A conical fused silica lens was used to further concentrate the solar radiation from the focal zone of a 2 m diameter primary concentrator to a Nd:YAG single-crystal rod within a conical pump cavity, which enabled multipass pumping to the active medium. A 56 W cw laser power was measured, corresponding to 21.1  W/m2 record-high solar laser collection efficiency with the heliostat–parabolic Mirror System. 4.9% slope efficiency was calculated, corresponding to 175% enhancement over our previous result.

  • solar pumped tem00 mode nd yag laser by a heliostat parabolic Mirror System
    Solar Energy Materials and Solar Cells, 2015
    Co-Authors: Dawei Liang, Joana Almeida, Claudia R Vistas, Emmanuel Guillot
    Abstract:

    Abstract Here we report a significant advance in solar-pumped laser beam brightness by pumping a 3 mm diameter Nd:YAG single-crystal rod with a heliostat-parabolic Mirror System. The incoming solar radiation is first collected and focused by the System. A rectangular fused silica light guide and a 2D-CPC concentrator are then combined to further compress the concentrated solar radiation into the laser rod within a V-shaped pumping cavity. 4.4 W continuous-wave TEM 00 mode ( M 2 ≤1.05) 1064 nm solar laser power is finally produced, attaining 4.0 W laser beam brightness figure of merit, which is 2.1 times higher than the previous record by a Fresnel lens. 0.81% TEM 00 mode laser slope efficiency is achieved.

  • a 40 w cw nd yag solar laser pumped through a heliostat a parabolic Mirror System
    Laser Physics, 2013
    Co-Authors: Joana Almeida, Dawei Liang, Emmanuel Guillot, Yasser A Abdelhadi
    Abstract:

    Solar-pumped solid-state lasers are promising for renewable extreme-temperature material processing. Here, we report a significant improvement in solar laser collection efficiency by pumping the most widely used Nd:YAG single-crystal rod through a heliostat?parabolic Mirror System. A conical-shaped fused silica light guide with 3D-CPC output end is used to both transmit and compress the concentrated solar radiation from the focal zone of a 2?m diameter parabolic Mirror to a 5?mm diameter Nd:YAG rod within a conical pump cavity, which enables multi-pass pumping through the laser rod. 40?W cw laser power is measured, corresponding to 13.9?W?m?2 record-high collection efficiency for the solar laser pumped through a heliostat?parabolic Mirror System. 2.9% slope efficiency is fitted, corresponding to 132% enhancement over that of our previous pumping scheme. A 209% reduction in threshold pump power is also registered.

Tim Salditt - One of the best experts on this subject based on the ideXlab platform.

  • focus characterization of the nanomax kirkpatrick baez Mirror System
    Journal of Synchrotron Radiation, 2019
    Co-Authors: Markus Osterhoff, Anna Lena Robisch, Jakob Soltau, Marina Eckermann, Sebastian Kalbfleisch, Dina Carbone, Ulf Johansson, Tim Salditt
    Abstract:

    The focusing and coherence properties of the NanoMAX Kirkpatrick–Baez Mirror System at the fourth-generation MAX IV synchrotron in Lund have been characterized. The direct measurement of nano-focused X-ray beams is possible by scanning of an X-ray waveguide, serving basically as an ultra-thin slit. In quasi-coherent operation, beam sizes of down to 56 nm (FWHM, horizontal direction) can be achieved. Comparing measured Airy-like fringe patterns with simulations, the degree of coherence |μ| has been quantified as a function of the secondary source aperture (SSA); the coherence is larger than 50% for SSA sizes below 11 µm at hard X-ray energies of 14 keV. For an SSA size of 5 µm, the degree of coherence has been determined to be 87%.

  • sub 5 nm hard x ray point focusing by a combined kirkpatrick baez Mirror and multilayer zone plate
    Optics Express, 2013
    Co-Authors: Florian Doring, Markus Osterhoff, Anna Lena Robisch, Christian Eberl, A Ruhlandt, Tobias Liese, Felix Schlenkrich, S Hoffmann, Matthias Bartels, Tim Salditt
    Abstract:

    Compound optics such as lens Systems can overcome the limitations concerning resolution, efficiency, or aberrations which fabrication constraints would impose on any single optical element. In this work we demonstrate unprecedented sub-5 nm point focusing of hard x-rays, based on the combination of a high gain Kirkpatrick-Baez (KB) Mirror System and a high resolution W/Si multilayer zone plate (MZP) for ultra-short focal length f. The pre-focusing allows limiting the MZP radius to below 2 μm, compatible with the required 5 nm structure width and essentially unlimited aspect ratios, provided by enabling fabrication technology based on pulsed laser deposition (PLD) and focused ion beam (FIB).

  • two dimensional hard x ray beam compression by combined focusing and waveguide optics
    Physical Review Letters, 2005
    Co-Authors: A Jarre, Christian Fuhse, C Ollinger, Jens Seeger, Remi Tucoulou, Tim Salditt
    Abstract:

    A two-dimensionally confining x-ray channel waveguide structure is combined with a high gain Kirkpatrick-Baez prefocusing Mirror System yielding a hard x-ray beam with a cross section of $25\ifmmode\times\else\texttimes\fi{}47\text{ }\text{ }{\mathrm{n}\mathrm{m}}^{2}$ (FWHM). Unlike the previously employed resonant beam coupling scheme, the incoming beam is coupled in from the front side of the waveguide and the waveguided beam is no longer accompanied by spurious reflected or transmitted beams. The field distribution in the waveguide channel has been calculated numerically. The calculated transmission and far-field intensity pattern are in good agreement with the experimental results.

Dawei Liang - One of the best experts on this subject based on the ideXlab platform.

  • 25 w m 2 collection efficiency solar pumped nd yag laser by a heliostat parabolic Mirror System
    Applied Optics, 2016
    Co-Authors: Dawei Liang, Joana Almeida, Claudia R Vistas
    Abstract:

    A large aspheric fused silica lens was used to couple efficiently the concentrated solar radiation from the focal zone of a 1.5-m-diameter primary concentrator into a 4-mm-diameter, 35-mm-long Nd:YAG single-crystal rod within a conical pump cavity. Continuous-wave laser power of 29.3 W was measured, attaining 25.0  W/m2 solar laser collection efficiency, corresponding to a 19% increase over the previous record. Its laser beam figure of merit—the ratio between laser power and the product of Mx2, My2 beam quality factors—of 0.01 W is 1.6 times higher than that of a direct tracking solar laser with 30  W/m2 collection efficiency. A strong dependency of solar laser power on laser resonator cavity length was found.

  • 5 5 w continuous wave tem 00 mode nd yag solar laser by a light guide 2v shaped pump cavity
    Applied Physics B, 2015
    Co-Authors: Joana Almeida, Dawei Liang, Claudia R Vistas, R Bouadjemine, Emmanuel Guillot
    Abstract:

    A significant progress in TEM00-mode solar laser power and efficiency with heliostat–parabolic Mirror System is reported here. A double-stage light-guide/2V-shaped pump cavity is used to efficiently couple and redistribute the concentrated pump light from a 2-m-diameter parabolic Mirror to a 4-mm-diameter, 30-mm-length, 1.1 at.% Nd:YAG single-crystal rod. The light guide with large rectangular cross section enables a stable uniform pumping profile along the laser rod, resulting also in an enhanced tracking error compensation capacity. 5.5 W cw TEM00-mode solar laser power was measured at the output of a thermally near unstable asymmetric resonator. 150 and 157 % improvement in TEM00-mode solar laser collection efficiency and slope efficiency were obtained, respectively.

  • 56 w cw nd yag solar laser by a heliostat parabolic Mirror System
    European Quantum Electronics Conference, 2015
    Co-Authors: Joana Almeida, Dawei Liang, Claudia R Vistas, Emmanuel Guillot
    Abstract:

    Solar-pumped lasers are natural candidates for applications where sunlight is plentiful and few other energy sources are available. Since the first report of “A sun-pumped cw one-watt laser” in 1966 [1], optical and laser material advances have continued to improve solar laser performance. Parabolic Mirrors have long been explored to achieve tight focusing of incoming solar radiation. However, their use for solar laser researches has been neglected in recent years due to the increased interests in large-size Fresnel lenses. Fresnel lens is cost-effective, but it causes the dispersion of the solar radiation along its focal zone, hampering the efficient light concentration to the laser rod. It is therefore valuable for us to carry out the solar laser research with parabolic Mirrors. A new progress in both solar laser collection efficiency and slope efficiency with heliostat - parabolic Mirror System is reported here.

  • highly efficient end side pumped nd yag solar laser by a heliostat parabolic Mirror System
    Applied Optics, 2015
    Co-Authors: Joana Almeida, Dawei Liang, Claudia R Vistas, Emmanuel Guillot
    Abstract:

    We report a large improvement in the collection and slope efficiency of an Nd:YAG solar laser pumped by a heliostat–parabolic Mirror System. A conical fused silica lens was used to further concentrate the solar radiation from the focal zone of a 2 m diameter primary concentrator to a Nd:YAG single-crystal rod within a conical pump cavity, which enabled multipass pumping to the active medium. A 56 W cw laser power was measured, corresponding to 21.1  W/m2 record-high solar laser collection efficiency with the heliostat–parabolic Mirror System. 4.9% slope efficiency was calculated, corresponding to 175% enhancement over our previous result.

  • solar pumped tem00 mode nd yag laser by a heliostat parabolic Mirror System
    Solar Energy Materials and Solar Cells, 2015
    Co-Authors: Dawei Liang, Joana Almeida, Claudia R Vistas, Emmanuel Guillot
    Abstract:

    Abstract Here we report a significant advance in solar-pumped laser beam brightness by pumping a 3 mm diameter Nd:YAG single-crystal rod with a heliostat-parabolic Mirror System. The incoming solar radiation is first collected and focused by the System. A rectangular fused silica light guide and a 2D-CPC concentrator are then combined to further compress the concentrated solar radiation into the laser rod within a V-shaped pumping cavity. 4.4 W continuous-wave TEM 00 mode ( M 2 ≤1.05) 1064 nm solar laser power is finally produced, attaining 4.0 W laser beam brightness figure of merit, which is 2.1 times higher than the previous record by a Fresnel lens. 0.81% TEM 00 mode laser slope efficiency is achieved.