The Experts below are selected from a list of 111 Experts worldwide ranked by ideXlab platform

Willem L. Vos - One of the best experts on this subject based on the ideXlab platform.

  • Fluorescence Lifetime of Emitters with Broad Homogeneous Linewidths Modified in Opal Photonic Crystals
    The Journal of Physical Chemistry C, 2008
    Co-Authors: Ivan S. Nikolaev, Peter Lodahl, Willem L. Vos
    Abstract:

    We have investigated the dynamics of spontaneous emission from dye molecules embedded in opal photonic Crystals. Fluorescence lifetimes of Rhodamine 6G (R6G) dye were measured as a function of both optical frequency and Crystal Lattice Parameter of the polystyrene opals. Due to the broad homogeneous line width of the dye, the observed fluorescence lifetime varies only slightly with the frequency within the dye emission spectrum. The lifetime however does change as a function of the Crystal Lattice Parameter. Our observations agree with theoretical calculations of the local density of optical states (LDOS) in the three-dimensional photonic Crystals. The experiments and theory taken together reveal that the emission lifetime is modified over frequency ranges that are broader than the homogeneous emission line width of R6G dye.

  • Color Control of Natural Fluorescent Proteins by Photonic Crystals
    Small (Weinheim an der Bergstrasse Germany), 2008
    Co-Authors: Christian Blum, Ivan S. Nikolaev, Allard Mosk, Vinod Subramaniam, Willem L. Vos
    Abstract:

    The emission of fluorescent proteins inside photonic Crystals is studied. It is demonstrated that the apparent emission color of the fluorescent protein can be controlled externally by the photonic Crystal. With increasing Crystal Lattice Parameter, the appearance of the proteins turns from orange to red, and suddenly to green. The dramatic color changes agree with the theoretically expected redistribution of light escaping around the stop band of the photonic Crystal. Our experiments show the potential of combining biological systems with nanophotonics. This "biophotonic engineering" may be extended to control emission rates and complex Förster energy-transfer systems obtained by protein engineering.

  • Dynamics of spontaneous emission controlled by local density of states in photonic Crystals
    2006 Conference on Lasers and Electro-Optics and 2006 Quantum Electronics and Laser Science Conference, 2006
    Co-Authors: Peter Lodahl, Ivan S. Nikolaev, A. Floris Van Driel, Willem L. Vos
    Abstract:

    We have measured time-resolved spontaneous emission from quantum dots in 3D photonic Crystals. Due to the spatially dependent local density of states, the distribution of decay rates varies strongly with the photonic Crystal Lattice Parameter.

  • Spontaneous-emission rate distributions in photonic Crystals controlled by position-dependent local density of states
    arXiv: Optics, 2005
    Co-Authors: Ivan S. Nikolaev, Peter Lodahl, A. Floris Van Driel, Willem L. Vos
    Abstract:

    We have measured spontaneous emission decay rates from an ensemble of quantum dots in strongly interacting inverse-opal photonic Crystals. The decay traces are successfully modelled with a log-normal distribution of decay rates. The most-frequent decay rate varies by a factor of three as a function of the Crystal Lattice Parameter, in agreement with the theoretical photonic density of states. The distribution width varies by a factor of six and can be identified with the spatial variation of the local density of states that is probed by quantum dots at various positions in the unit cell. This is the first experimental evidence for a position-dependent emission rate in photonic Crystals.

Ivan S. Nikolaev - One of the best experts on this subject based on the ideXlab platform.

  • Fluorescence Lifetime of Emitters with Broad Homogeneous Linewidths Modified in Opal Photonic Crystals
    The Journal of Physical Chemistry C, 2008
    Co-Authors: Ivan S. Nikolaev, Peter Lodahl, Willem L. Vos
    Abstract:

    We have investigated the dynamics of spontaneous emission from dye molecules embedded in opal photonic Crystals. Fluorescence lifetimes of Rhodamine 6G (R6G) dye were measured as a function of both optical frequency and Crystal Lattice Parameter of the polystyrene opals. Due to the broad homogeneous line width of the dye, the observed fluorescence lifetime varies only slightly with the frequency within the dye emission spectrum. The lifetime however does change as a function of the Crystal Lattice Parameter. Our observations agree with theoretical calculations of the local density of optical states (LDOS) in the three-dimensional photonic Crystals. The experiments and theory taken together reveal that the emission lifetime is modified over frequency ranges that are broader than the homogeneous emission line width of R6G dye.

  • Color Control of Natural Fluorescent Proteins by Photonic Crystals
    Small (Weinheim an der Bergstrasse Germany), 2008
    Co-Authors: Christian Blum, Ivan S. Nikolaev, Allard Mosk, Vinod Subramaniam, Willem L. Vos
    Abstract:

    The emission of fluorescent proteins inside photonic Crystals is studied. It is demonstrated that the apparent emission color of the fluorescent protein can be controlled externally by the photonic Crystal. With increasing Crystal Lattice Parameter, the appearance of the proteins turns from orange to red, and suddenly to green. The dramatic color changes agree with the theoretically expected redistribution of light escaping around the stop band of the photonic Crystal. Our experiments show the potential of combining biological systems with nanophotonics. This "biophotonic engineering" may be extended to control emission rates and complex Förster energy-transfer systems obtained by protein engineering.

  • Dynamics of spontaneous emission controlled by local density of states in photonic Crystals
    2006 Conference on Lasers and Electro-Optics and 2006 Quantum Electronics and Laser Science Conference, 2006
    Co-Authors: Peter Lodahl, Ivan S. Nikolaev, A. Floris Van Driel, Willem L. Vos
    Abstract:

    We have measured time-resolved spontaneous emission from quantum dots in 3D photonic Crystals. Due to the spatially dependent local density of states, the distribution of decay rates varies strongly with the photonic Crystal Lattice Parameter.

  • Spontaneous-emission rate distributions in photonic Crystals controlled by position-dependent local density of states
    arXiv: Optics, 2005
    Co-Authors: Ivan S. Nikolaev, Peter Lodahl, A. Floris Van Driel, Willem L. Vos
    Abstract:

    We have measured spontaneous emission decay rates from an ensemble of quantum dots in strongly interacting inverse-opal photonic Crystals. The decay traces are successfully modelled with a log-normal distribution of decay rates. The most-frequent decay rate varies by a factor of three as a function of the Crystal Lattice Parameter, in agreement with the theoretical photonic density of states. The distribution width varies by a factor of six and can be identified with the spatial variation of the local density of states that is probed by quantum dots at various positions in the unit cell. This is the first experimental evidence for a position-dependent emission rate in photonic Crystals.

Caixia Sun - One of the best experts on this subject based on the ideXlab platform.

  • Internal Polarization Modulation in Bi2MoO6 for Photocatalytic Performance Enhancement under Visible‐Light Illumination
    ChemSusChem, 2018
    Co-Authors: Chen Yan, Weiyi Yang, Shuang Gao, Linggang Zhu, Caixia Sun
    Abstract:

    A built-in electric field from polarization inside polar photocatalysts could provide the driving force for photogenerated electrons and holes to move in opposite directions for better separation to improve their photocatalytic performance. The photocatalytic performance of a polar photocatalyst of Bi2 MoO6 has been enhanced through the precise control of its structure to increase internal polarization. DFT calculations predicted that a shortened Crystal Lattice Parameter b in Bi2 MoO6 could induce larger internal polarization, which was achieved by the modulation of the pH of the reaction solution during a solvothermal synthetic process. A series of Bi2 MoO6 samples were created with reaction solutions of pH≈1, 4, and 8; the Crystal Lattice Parameter b was found to decrease gradually with increasing solution pH. Accordingly, these Bi2 MoO6 samples demonstrated a gradually enhanced photocatalytic performance with decreasing Crystal Lattice Parameter b, as demonstrated by the photocatalytic degradation of sulfamethoxazole/phenol and disinfection of Staphylococcus aureus bacteria under visible-light illumination due to improved photogenerated charge-carrier separation. This study demonstrates an innovative design strategy for materials to further enhance the photocatalytic performance of polar photocatalysts for a broad range of technical applications.

Peter Lodahl - One of the best experts on this subject based on the ideXlab platform.

  • Fluorescence Lifetime of Emitters with Broad Homogeneous Linewidths Modified in Opal Photonic Crystals
    The Journal of Physical Chemistry C, 2008
    Co-Authors: Ivan S. Nikolaev, Peter Lodahl, Willem L. Vos
    Abstract:

    We have investigated the dynamics of spontaneous emission from dye molecules embedded in opal photonic Crystals. Fluorescence lifetimes of Rhodamine 6G (R6G) dye were measured as a function of both optical frequency and Crystal Lattice Parameter of the polystyrene opals. Due to the broad homogeneous line width of the dye, the observed fluorescence lifetime varies only slightly with the frequency within the dye emission spectrum. The lifetime however does change as a function of the Crystal Lattice Parameter. Our observations agree with theoretical calculations of the local density of optical states (LDOS) in the three-dimensional photonic Crystals. The experiments and theory taken together reveal that the emission lifetime is modified over frequency ranges that are broader than the homogeneous emission line width of R6G dye.

  • Dynamics of spontaneous emission controlled by local density of states in photonic Crystals
    2006 Conference on Lasers and Electro-Optics and 2006 Quantum Electronics and Laser Science Conference, 2006
    Co-Authors: Peter Lodahl, Ivan S. Nikolaev, A. Floris Van Driel, Willem L. Vos
    Abstract:

    We have measured time-resolved spontaneous emission from quantum dots in 3D photonic Crystals. Due to the spatially dependent local density of states, the distribution of decay rates varies strongly with the photonic Crystal Lattice Parameter.

  • Spontaneous-emission rate distributions in photonic Crystals controlled by position-dependent local density of states
    arXiv: Optics, 2005
    Co-Authors: Ivan S. Nikolaev, Peter Lodahl, A. Floris Van Driel, Willem L. Vos
    Abstract:

    We have measured spontaneous emission decay rates from an ensemble of quantum dots in strongly interacting inverse-opal photonic Crystals. The decay traces are successfully modelled with a log-normal distribution of decay rates. The most-frequent decay rate varies by a factor of three as a function of the Crystal Lattice Parameter, in agreement with the theoretical photonic density of states. The distribution width varies by a factor of six and can be identified with the spatial variation of the local density of states that is probed by quantum dots at various positions in the unit cell. This is the first experimental evidence for a position-dependent emission rate in photonic Crystals.

X. F. Huang - One of the best experts on this subject based on the ideXlab platform.

  • Influences of Sr dose on the Crystal structure Parameters and Sr distributions of Sr-incorporated hydroxyapatite
    Journal of biomedical materials research. Part B Applied biomaterials, 2013
    Co-Authors: D.g. Guo, Y. Z. Hao, C. Q. Fang, L. J. Sun, Hui Zhu, J. Wang, X. F. Huang
    Abstract:

    Stoichiometric strontium-incorporated hydroxyapatite (Sr-HA) with different Sr concentrations [Sr/(Sr+Ca)] were synthesized using a wet chemical approach and characterized by X-ray diffraction, Fourier-transformed infrared absorption, X-ray photoelectron spectroscopy, and Rietveld Structure Refinement. The Crystal Lattice Parameter, Sr distribution, chemical state of Sr, and also the relationships between their variations and the Sr concentrations have been intensively studied. The results show that both the Crystal Lattice Parameters and Crystal plane space of Sr-HA remarkably increase with the Sr concentration increasing. Whether Sr preferably occupies the Ca(I) site or Ca(II) site after incorporated into apatite Lattice depends on the Sr number incorporated into apatite. All the Sr ions completely occupy the Ca(II) sites when the Sr concentration is below 5%. With the exception of partial Sr ions occupying the Ca(II) sites, the other Sr ions start to occupy the Ca(I) sites when the Sr concentration doped in HA is beyond 10%. The ratio of Sr ions occupying the Ca(I) sites increases with the further raising Sr concentration up to 20%. The Sr ions inherit the chemical state and environment of the original Ca(I) or Ca(II) site after incorporated into apatite. © 2013 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 101B: 1275–1283, 2013.