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D J Richardson - One of the best experts on this subject based on the ideXlab platform.

  • nondestructive measurement of the roughness of the inner surface of hollow Core photonic bandgap fibers
    Optics Letters, 2016
    Co-Authors: Xavier Buet, C Brun, Jerome Gâteau, Bruno Bresson, S R Sandoghchi, Eric Numkam Fokoua, M N Petrovich, F Poletti, D J Richardson, Damien Vandembroucq
    Abstract:

    We present optical and atomic force microscopy measurements of the roughness of the Core Wall surface within a hollow Core photonic bandgap fiber (HC-PBGF) over the [3×10-2 µm-1 to 30 µm-1] spatial frequency range. A recently developed immersion optical profilometry technique with picometer-scale sensitivity was used to measure the roughness of air-glass surfaces inside the fiber at unprecedentedly low spatial frequencies, which are known to have the highest impact on HC-PBGF scattering loss and, thus, determine their loss limit. Optical access to the inner surface of the Core was obtained by the selective filling of the cladding holes with index matching liquid using techniques borrowed from micro-fluidics. Both measurement techniques reveal ultralow roughness levels exhibiting a 1/f spectral power density dependency characteristic of frozen surface capillary waves over a broad spatial frequency range. However, a deviation from this behavior at low spatial frequencies was observed for the first time, to the best of our knowledge.

  • low loss and low bend sensitivity mid infrared guidance in a hollow Core photonic bandgap fiber
    Optics Letters, 2014
    Co-Authors: N V Wheeler, S R Sandoghchi, Eric Numkam Fokoua, M N Petrovich, Alexander M Heidt, N K Baddela, J R Hayes, Francesco Poletti, D J Richardson
    Abstract:

    Hollow-Core-photonic-bandgap fiber, fabricated from high-purity synthetic silica, with a wide operating bandwidth between 3.1 and 3.7 μm, is reported. A minimum attenuation of 0.13 dB/m is achieved through a 19-cell Core design with a thin Core Wall surround. The loss is reduced further to 0.05 dB/m following a purging process to remove hydrogen chloride gas from the fiber-representing more than an order of magnitude loss reduction as compared to previously reported bandgap-guiding fibers operating in the mid-infrared. The fiber also offers a low bend sensitivity of <0.25 dB per 5 cm diameter turn over a 300 nm bandwidth. Simulations are in good agreement with the achieved losses and indicate that a further loss reduction of more than a factor of 2 should be possible by enlarging the Core using a 37-cell design.

S R Sandoghchi - One of the best experts on this subject based on the ideXlab platform.

  • nondestructive measurement of the roughness of the inner surface of hollow Core photonic bandgap fibers
    Optics Letters, 2016
    Co-Authors: Xavier Buet, C Brun, Jerome Gâteau, Bruno Bresson, S R Sandoghchi, Eric Numkam Fokoua, M N Petrovich, F Poletti, D J Richardson, Damien Vandembroucq
    Abstract:

    We present optical and atomic force microscopy measurements of the roughness of the Core Wall surface within a hollow Core photonic bandgap fiber (HC-PBGF) over the [3×10-2 µm-1 to 30 µm-1] spatial frequency range. A recently developed immersion optical profilometry technique with picometer-scale sensitivity was used to measure the roughness of air-glass surfaces inside the fiber at unprecedentedly low spatial frequencies, which are known to have the highest impact on HC-PBGF scattering loss and, thus, determine their loss limit. Optical access to the inner surface of the Core was obtained by the selective filling of the cladding holes with index matching liquid using techniques borrowed from micro-fluidics. Both measurement techniques reveal ultralow roughness levels exhibiting a 1/f spectral power density dependency characteristic of frozen surface capillary waves over a broad spatial frequency range. However, a deviation from this behavior at low spatial frequencies was observed for the first time, to the best of our knowledge.

  • low loss and low bend sensitivity mid infrared guidance in a hollow Core photonic bandgap fiber
    Optics Letters, 2014
    Co-Authors: N V Wheeler, S R Sandoghchi, Eric Numkam Fokoua, M N Petrovich, Alexander M Heidt, N K Baddela, J R Hayes, Francesco Poletti, D J Richardson
    Abstract:

    Hollow-Core-photonic-bandgap fiber, fabricated from high-purity synthetic silica, with a wide operating bandwidth between 3.1 and 3.7 μm, is reported. A minimum attenuation of 0.13 dB/m is achieved through a 19-cell Core design with a thin Core Wall surround. The loss is reduced further to 0.05 dB/m following a purging process to remove hydrogen chloride gas from the fiber-representing more than an order of magnitude loss reduction as compared to previously reported bandgap-guiding fibers operating in the mid-infrared. The fiber also offers a low bend sensitivity of <0.25 dB per 5 cm diameter turn over a 300 nm bandwidth. Simulations are in good agreement with the achieved losses and indicate that a further loss reduction of more than a factor of 2 should be possible by enlarging the Core using a 37-cell design.

M N Petrovich - One of the best experts on this subject based on the ideXlab platform.

  • nondestructive measurement of the roughness of the inner surface of hollow Core photonic bandgap fibers
    Optics Letters, 2016
    Co-Authors: Xavier Buet, C Brun, Jerome Gâteau, Bruno Bresson, S R Sandoghchi, Eric Numkam Fokoua, M N Petrovich, F Poletti, D J Richardson, Damien Vandembroucq
    Abstract:

    We present optical and atomic force microscopy measurements of the roughness of the Core Wall surface within a hollow Core photonic bandgap fiber (HC-PBGF) over the [3×10-2 µm-1 to 30 µm-1] spatial frequency range. A recently developed immersion optical profilometry technique with picometer-scale sensitivity was used to measure the roughness of air-glass surfaces inside the fiber at unprecedentedly low spatial frequencies, which are known to have the highest impact on HC-PBGF scattering loss and, thus, determine their loss limit. Optical access to the inner surface of the Core was obtained by the selective filling of the cladding holes with index matching liquid using techniques borrowed from micro-fluidics. Both measurement techniques reveal ultralow roughness levels exhibiting a 1/f spectral power density dependency characteristic of frozen surface capillary waves over a broad spatial frequency range. However, a deviation from this behavior at low spatial frequencies was observed for the first time, to the best of our knowledge.

  • low loss and low bend sensitivity mid infrared guidance in a hollow Core photonic bandgap fiber
    Optics Letters, 2014
    Co-Authors: N V Wheeler, S R Sandoghchi, Eric Numkam Fokoua, M N Petrovich, Alexander M Heidt, N K Baddela, J R Hayes, Francesco Poletti, D J Richardson
    Abstract:

    Hollow-Core-photonic-bandgap fiber, fabricated from high-purity synthetic silica, with a wide operating bandwidth between 3.1 and 3.7 μm, is reported. A minimum attenuation of 0.13 dB/m is achieved through a 19-cell Core design with a thin Core Wall surround. The loss is reduced further to 0.05 dB/m following a purging process to remove hydrogen chloride gas from the fiber-representing more than an order of magnitude loss reduction as compared to previously reported bandgap-guiding fibers operating in the mid-infrared. The fiber also offers a low bend sensitivity of <0.25 dB per 5 cm diameter turn over a 300 nm bandwidth. Simulations are in good agreement with the achieved losses and indicate that a further loss reduction of more than a factor of 2 should be possible by enlarging the Core using a 37-cell design.

Eric Numkam Fokoua - One of the best experts on this subject based on the ideXlab platform.

  • nondestructive measurement of the roughness of the inner surface of hollow Core photonic bandgap fibers
    Optics Letters, 2016
    Co-Authors: Xavier Buet, C Brun, Jerome Gâteau, Bruno Bresson, S R Sandoghchi, Eric Numkam Fokoua, M N Petrovich, F Poletti, D J Richardson, Damien Vandembroucq
    Abstract:

    We present optical and atomic force microscopy measurements of the roughness of the Core Wall surface within a hollow Core photonic bandgap fiber (HC-PBGF) over the [3×10-2 µm-1 to 30 µm-1] spatial frequency range. A recently developed immersion optical profilometry technique with picometer-scale sensitivity was used to measure the roughness of air-glass surfaces inside the fiber at unprecedentedly low spatial frequencies, which are known to have the highest impact on HC-PBGF scattering loss and, thus, determine their loss limit. Optical access to the inner surface of the Core was obtained by the selective filling of the cladding holes with index matching liquid using techniques borrowed from micro-fluidics. Both measurement techniques reveal ultralow roughness levels exhibiting a 1/f spectral power density dependency characteristic of frozen surface capillary waves over a broad spatial frequency range. However, a deviation from this behavior at low spatial frequencies was observed for the first time, to the best of our knowledge.

  • low loss and low bend sensitivity mid infrared guidance in a hollow Core photonic bandgap fiber
    Optics Letters, 2014
    Co-Authors: N V Wheeler, S R Sandoghchi, Eric Numkam Fokoua, M N Petrovich, Alexander M Heidt, N K Baddela, J R Hayes, Francesco Poletti, D J Richardson
    Abstract:

    Hollow-Core-photonic-bandgap fiber, fabricated from high-purity synthetic silica, with a wide operating bandwidth between 3.1 and 3.7 μm, is reported. A minimum attenuation of 0.13 dB/m is achieved through a 19-cell Core design with a thin Core Wall surround. The loss is reduced further to 0.05 dB/m following a purging process to remove hydrogen chloride gas from the fiber-representing more than an order of magnitude loss reduction as compared to previously reported bandgap-guiding fibers operating in the mid-infrared. The fiber also offers a low bend sensitivity of <0.25 dB per 5 cm diameter turn over a 300 nm bandwidth. Simulations are in good agreement with the achieved losses and indicate that a further loss reduction of more than a factor of 2 should be possible by enlarging the Core using a 37-cell design.

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

  • ground state atomic polarization relaxation time measurement of rb filled hypocycloidal Core shaped kagome hc pcf
    Journal of Physics B, 2016
    Co-Authors: T D Bradley, J J Mcferran, Ekaterina Ilinova, Jenny Jouin, Philippe Thomas, Benoit Debord, M Alharbi, Frederic Gerome, F Benabid
    Abstract:

    We report on the measurement of ground-state atomic polarization relaxation time of Rb vapor confined in five different hypocycloidal Core-shape Kagome hollow-Core photonic crystal fibers made with uncoated silica glass. We are able to distinguish between Wall-collision and transit-time effects in an optical waveguide and deduce the contribution of the atom's dwell time at the Core Wall surface. In contrast with conventional macroscopic atomic cell configuration, and in agreement with Monte Carlo simulations, the measured relaxation times were found to be at least one order of magnitude longer than the limit set by atom-Wall collisional from thermal atoms. This extended relaxation time is explained by the combination of a stronger contribution of the slow atoms in the atomic polarization build-up, and of the relatively significant contribution of dwell time to the relaxation process of the ground state polarization.

  • ground state atomic polarization relaxation time measurement of rb filled hypocycloidal Core shaped kagome hc pcf
    arXiv: Atomic Physics, 2015
    Co-Authors: T D Bradley, J J Mcferran, Ekaterina Ilinova, Jenny Jouin, Philippe Thomas, Benoit Debord, M Alharbi, Frederic Gerome, F Benabid
    Abstract:

    We report on the measurement of ground state atomic polarization relaxation tile of Rb vapor confined in five different hypocycloidal Core shape Kagome hollow Core photonic crystal fibers made with uncoated silica glass. We are able to distinguish between Wall-collision and transit-time effects in optical waveguide and deduce the contribution of the atom's dwell time at the Core Wall surface. In contrast with convetional macroscopic atomic cell configuration, and in agreement with Monte Carlo simulations, the measured relaxation times were found to be at least one order of magnitude longer than the limit set by the atom-Wall collisional relaxation from thermal atoms. This extended relaxation time is explained by the combination of a stronger contribution of the slow atoms in the atomic polarization build-up, and of the relatively significant contribution of dwell time to the relaxation process of the ground state polarization.