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

  • reflectivity of three dimensional gaas Photonic Band Gap crystals of finite thickness
    Physical Review B, 2020
    Co-Authors: Cornelis A.m. Harteveld, Takeyoshi Tajiri, Shun Takahashi, Yasuhiko Arakawa, Satoshi Iwamoto, Willem L. Vos
    Abstract:

    We study the optical reflectivity of real three-dimensional (3D) Photonic Band-Gap crystals with increasing thickness. The crystals consist of GaAs plates with nanorod arrays that are assembled by an advanced stacking method into high-quality 3D woodpile structures. We observe intense and broad reflectivity peaks with stop Bands that correspond to a broad Gap in the Photonic Band structures. The maximum reflectivity quickly reaches high values, even for a few crystal layers. Remarkably, the Bandwidth of the stop Bands hardly decreases with increasing crystal thickness, in good agreement with finite-difference time domain (FDTD) simulations. This behavior differs remarkably from the large changes observed earlier in weakly interacting 3D Photonic crystals. The nearly constant Bandwidth and high reflectivity are rationalized by multiple Bragg interference that occurs in strongly interacting Photonic Band-Gap crystals, whereby the incident light scatters from multiple reciprocal lattice vectors simultaneously, in particular, from oblique ones that are parallel to a longer crystal dimension and thus experience hardly any finite-size effects. Our insights have favorable consequences for the application of 3D Photonic Band-Gap crystals, notably since even thin structures reveal the full Band-Gap functionality, including devices that shield quantum bits from vacuum fluctuations.

  • Experimental probe of a complete 3D Photonic Band Gap.
    Optics Express, 2020
    Co-Authors: Manashee Adhikary, Ravitej Uppu, Cornelis A.m. Harteveld, Diana Grishina, Willem L. Vos
    Abstract:

    The identification of a complete three-dimensional (3D) Photonic Band Gap in real crystals typically employs theoretical or numerical models that invoke idealized crystal structures. Such an approach is prone to false positives (Gap wrongly assigned) or false negatives (Gap missed). Therefore, we propose a purely experimental probe of the 3D Photonic Band Gap that pertains to any class of Photonic crystals. We collect reflectivity spectra with a large aperture on exemplary 3D inverse woodpile structures that consist of two perpendicular nanopore arrays etched in silicon. We observe intense reflectivity peaks (R>90%) typical of high-quality crystals with broad stopBands. A resulting parametric plot of s-polarized versus p-polarized stopBand width is linear ("y=x"), a characteristic of a 3D Photonic Band Gap, as confirmed by simulations. By scanning the focus across the crystal, we track the polarization-resolved stopBands versus the volume fraction of high-index material and obtain many more parametric data to confirm that the high-NA stopBand corresponds to the Photonic Band Gap. This practical probe is model-free and provides fast feedback on the advanced nanofabrication needed for 3D Photonic crystals and stimulates practical applications of Band Gaps in 3D silicon nanoPhotonics and Photonic integrated circuits, photovoltaics, cavity QED, and quantum information processing.

  • Experimental probe of a complete 3D Photonic Band Gap
    Optics express, 2020
    Co-Authors: Manashee Adhikary, Ravitej Uppu, Cornelis A.m. Harteveld, Diana Grishina, Willem L. Vos
    Abstract:

    The identification of a complete three-dimensional (3D) Photonic Band Gap in real crystals always employs theoretical or numerical models that invoke idealized crystal structures. Thus, this approach is prone to false positives (Gap wrongly assigned) or false negatives (Gap missed). Therefore, we propose a purely experimental probe of the 3D Photonic Band Gap that pertains to many different classes of Photonic materials. We study position and polarization-resolved reflectivity spectra of 3D inverse woodpile structures that consist of two perpendicular nanopore arrays etched in silicon. We observe intense reflectivity peaks $(R > 90\%)$ typical of high-quality crystals with broad stopBands. We track the stopBand width versus pore radius, which agrees much better with the predicted 3D Photonic Band Gap than with a directional stop Gap on account of the large numerical aperture used. A parametric plot of s-polarized versus p-polarized stopBand width agrees very well with the 3D Band Gap and is model-free. This practical probe provides fast feedback on the advanced nanofabrication needed for 3D Photonic crystals and stimulates practical applications of Band Gaps in 3D silicon nanoPhotonics and Photonic integrated circuits, photovoltaics, cavity QED, and quantum information processing.

  • inhibited spontaneous emission of quantum dots observed in a 3d Photonic Band Gap
    Physical Review Letters, 2011
    Co-Authors: S.r. Huisman, M. D. Leistikow, Allard Mosk, Elahe Yeganegi, Ad Lagendijk, Willem L. Vos
    Abstract:

    We present time-resolved emission experiments of semiconductor quantum dots in silicon 3D inverse-woodpile Photonic Band Gap crystals. A systematic study is made of crystals with a range of pore radii to tune the Band Gap relative to the emission frequency. The decay rates averaged over all dipole orientations are inhibited by a factor of 10 in the Photonic Band Gap and enhanced up to 2× outside the Gap, in agreement with theory. We discuss the effects of spatial inhomogeneity, nonradiative decay, and transition dipole orientations on the observed inhibition in the Band Gap.

  • Experimental signature of a broad 3D Photonic Band Gap in silicon nanostructures
    2011 Conference on Lasers and Electro-Optics Europe and 12th European Quantum Electronics Conference (CLEO EUROPE EQEC), 2011
    Co-Authors: S.r. Huisman, R.v. Nair, Léon A. Woldering, M. D. Leistikow, Allard Mosk, Willem L. Vos
    Abstract:

    Three-dimensional Photonic crystals radically control propagation and emission of light [1, 2]. Photonic crystals are ordered composite materials with a spatially varying dielectric constant that has a periodicity of the order of the wavelength of light. In specific three-dimensional crystals, a common frequency range for all polarizations is formed for which light is not allowed to propagate in any direction, called the Photonic Band Gap. It is an outstanding challenge to create these crystals and experimentally demonstrate the Photonic Band Gap.

K. W. Koch - One of the best experts on this subject based on the ideXlab platform.

  • Review of Progress in Photonic Band-Gap Fibers
    Frontiers in Optics 2007 Laser Science XXIII Organic Materials and Devices for Displays and Energy Conversion, 2007
    Co-Authors: K. W. Koch
    Abstract:

    The unique properties of air-core Photonic Band-Gap fibers and their underlying principles of operation are reviewed. In addition, applications and other opportunities for these fibers are reviewed. Article not available.

  • soliton pulse compression in Photonic Band Gap fibers
    Optics Express, 2005
    Co-Authors: Dimitre G Ouzounov, Christopher J Hensley, Alexander L Gaeta, Natesan Venkateraman, Michael T Gallagher, K. W. Koch
    Abstract:

    We report on pulse compression using a hollow-core Photonic Band-Gap fiber filled with Xe. Output pulses with megawatt peak powers and durations of 50 fs have been generated from 120-fs input pulses. The large third-order dispersion inherent in these fibers degrades the optimal compression ratio and prevents generation of even shorter pulses. Nevertheless, for picosecond input pulses, compression to less than 100 fs is predicted.

  • surface modes in air core Photonic Band Gap fibers
    Optics Express, 2004
    Co-Authors: James A West, Nicholas F Borrelli, Charlene M Smith, Douglas C Allan, K. W. Koch
    Abstract:

    We present a detailed description of the role of surface modes in Photonic Band-Gap fibers (PBGFs). A model is developed that connects the experimental observations of high losses in the middle of the transmission spectrum to the presence of surface modes supported at the core-cladding interface. Furthermore, a new PBGF design is proposed that avoids these surface modes and produces single-mode operation.

  • Photonic Band-Gap fiber: Fiber of the future?
    LEOS Summer Topical Meeting, 2003
    Co-Authors: J.a. West, M. T. Gallagher, D.c. Allan, Natesan Venkataraman, C. M. Smith, D. Müller, Nicholas F Borrelli, K. W. Koch
    Abstract:

    We briefly review the state-of-the art in Photonic Band-Gap fibers. Recent reduction in attenuation to 13 dB/km demonstrates the potential of these hollow-core fibers to provide low-loss and low-nonlinearity for a variety of applications including transmission fiber.

Sajeev John - One of the best experts on this subject based on the ideXlab platform.

  • Photonic Band Gap Materials: Nonlinear Optics with Trapped Light
    Advances in Optical Sciences Congress, 2009
    Co-Authors: Sajeev John
    Abstract:

    I discuss quantum dot inversion, switching, and nonlinear optical Bloch-vector dynamics in the structured electromagnetic vacuum of a Photonic Band Gap waveguide. This offers a theoretical foundation for on-chip multi-wavelength-channel optical transistor action. Article not Available.

  • Electromagnetically induced exciton mobility in a Photonic Band Gap.
    Physical Review Letters, 2007
    Co-Authors: Sajeev John, Shengjun Yang
    Abstract:

    It is suggested that an exciton in the engineered vacuum of a Photonic-Band-Gap-quantum-well heterostructure exhibits electromagnetically induced anomalous quantum dynamics. The exciton is dressed by coherent emission and reabsorption of virtual photons near the Photonic Band edge and captured in momentum space, lowering its energy by 1-10 meV and lowering its effective mass by 4-5 orders of magnitude. The Photonic Band Gap simultaneously enables strong coupling to confined optical modes and long exciton lifetime.

  • Photonic Band Gap architectures for holographic lithography
    Physical Review Letters, 2004
    Co-Authors: Ovidiu Toader, Timothy Y M Chan, Sajeev John
    Abstract:

    Using symmetry considerations, we identify three families of large Photonic Band-Gap (PBG) architectures defined by the isointensity surfaces of four beam laser interference. For particular choices of beam intensities, directions, and polarizations, we obtain a diamondlike crystal, a novel body-centered cubic architecture, and a simple cubic structure with PBG to center frequency ratios of 25%, 21%, and 11%, respectively, when the isointensity surface defines a silicon (dielectric constant of 11.9) to air boundary.

  • Nonlinear optical solitary waves in a Photonic Band Gap
    Physical review letters, 1993
    Co-Authors: Sajeev John, Neset Akozbek
    Abstract:

    It is suggested that solitary wave solutions exist in the Gap region of Photonic Band Gap materials with a Kerr nonlinearity. Using a variational trial function we estimate the amplitude, size scale, and the nature of phase modulation of these nonlinear waves. In two dimensions, we predict the occurrence of a variety of finite energy solitary waves associated with the different symmetry points of the crystalline Brillouin zone. Solutions which preserve the symmetry of the crystal exist for both positive and negative Kerr coefficient whereas solutions which break the symmetry occur only for positive nonlinearity. These states are relevant to the bistable switching properties of Photonic Band Gap materials.

Mahi R. Singh - One of the best experts on this subject based on the ideXlab platform.

  • Dipole-dipole interaction in Photonic-Band-Gap materials doped with nanoparticles
    Physical Review A, 2007
    Co-Authors: Mahi R. Singh
    Abstract:

    A theory of linear susceptibility has been developed in the presence of dipole-dipole interaction for Photonic-Band-Gap (PBG) materials doped with an ensemble of five-level nanoparticles. An external probe laser induces dipole moments in nanoparticles. When the concentration of the particles is high, the induced dipoles interact with one another through dipole-dipole interaction. Mean-field theory is used to include the effect of dipole-dipole interaction in the calculation of susceptibility. Numerical simulations are performed for the real and imaginary susceptibilities and it is found that the system switches between inversionless and noninversionless states. In addition the system switches between absorptionless and nonabsorptionless states. These occur when the resonance energy lies near the valence-Band edge of the Photonic-Band-Gap material. The theory also predicts a polarization catastrophe in PBG materials doped with nanoparticles.

  • Controlling spontaneous emission in Photonic-Band-Gap materials doped with nanoparticles
    Physical Review A, 2007
    Co-Authors: Mahi R. Singh
    Abstract:

    The phenomenon of spontaneous emission cancellation has been investigated in Photonic-Band-Gap materials in the presence of dipole-dipole interaction. The material is densely doped with an ensemble of five-level nanoparticles. The mean field theory is used to calculate the effect of the dipole-dipole interaction whereas the linear response theory is used to calculate the expressions for the real and imaginary susceptibilities. Numerical simulations are performed for an isotropic Photonic-Band-Gap material. Interesting results are predicted such as the control of the spontaneous emission cancellation by moving the resonance energies between the energy Band and energy Gap. It is also found that the Photonic-Band-Gap material can be switched between absorptive and nonabsorptive states by changing the strength of the dipole-dipole interaction and the resonance energies in the energy Band.

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

  • Resonant and slow light self-collimation in Photonic Band Gap metamaterials
    2012
    Co-Authors: Emmanuel Centeno, Rémi Pollès, Julien Arlandis, Antoine Moreau
    Abstract:

    This study deals with in Photonic Band Gap materials based on metamaterials properties that consist in a periodic set of positive and negative index layers. These structures present new optical properties such as a zero-n Gap, zero-phase delay transmission and self-collimation effect. Here, we theoretically demonstrate that self-collimation can be render resonant or combines with slow light regime in Photonic Band Gap metamaterials.

  • Superlattice for Photonic Band Gap opening in monolayers of dielectric spheres
    Optics Express, 2006
    Co-Authors: Kevin Vynck, David Cassagne, Emmanuel Centeno
    Abstract:

    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.

  • Superlattice for Photonic Band Gap opening in monolayers of dielectric spheres
    Optics Express, 2006
    Co-Authors: Kevin Vynck, David Cassagne, Emmanuel Centeno
    Abstract:

    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.