• Title/Summary/Keyword: Photonic Crystal

Search Result 324, Processing Time 0.032 seconds

Tunable Slow Light with Large Bandwidth and Low-dispersion in Photonic Crystal Waveguide Infiltrated with Magnetic Fluids

  • Lei, Weizheng;Pu, Shengli
    • Journal of Magnetics
    • /
    • v.20 no.2
    • /
    • pp.110-113
    • /
    • 2015
  • Two kinds of magnetic fluids with different volume fractions are symmetrically filled into the W0.9 photonic crystal waveguide structure. The 2D plane-wave expansion method is used to investigate the slow light properties numerically. The constant group index criterion is employed to evaluate the slow light performance. The wavelength bandwidth ${\Delta}{\lambda}$ centering at ${\lambda}_0=1550nm$ varies from 32.4 to 44.2 nm when the magnetic field factor ${\alpha}_{\parallel}$ changes from 0 to 1. And the corresponding normalized delay bandwidth product can be tuned from 0.221 to 0.258. For comparison and optimization, two infiltration cases are investigated and the more advantageous infiltration scheme is found.

Huge Enhancement of Magneto-optical Kerr Effect of One-dimensional Photonic Crystals with a Ferromagnetic Defect Layer

  • Mitsuteru Inoue;Arai, Ken-Ichi;Toshitaka Fujii;Masanori Abe
    • The Korean Journal of Ceramics
    • /
    • v.6 no.4
    • /
    • pp.408-411
    • /
    • 2000
  • Although the rotation angle and its spectrum of the magneto-optical Kerr effect are physical quantities determined inherently by the material itself, we found that they can widely be designed by utilizing a one-dimensional photonic crystal with a ferromagnetic defect layer. By suitable choice of the film structure, the rotation angle at a designated narrow wavelength is resonantly enhanced up to as several hundred times larger as ordinary rotation angle of the magnetic. This is originated by the localization of light at the magnetic layer inside the film.

  • PDF

Small Group Velocity of Line Defect in Two-dimensional Photonic Crystal (2차원 광결정 선결함의 낮은 군속도)

  • Lee, Myoung-Rae;Kim, Gyeong-Rae;Shin, Won-Jin;Kim, Chang-Kyo;Hong, Chin-Soo
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
    • /
    • v.23 no.2
    • /
    • pp.128-132
    • /
    • 2010
  • Photonic crystal is dielectric materials or a set of different dielectric materials with periodic structure. Line defect is obtained by leaving out a row of rods along the $\Gamma$-X direction. We showed the change of group velocity in waveguide mode and found resultant small group velocity. Characteristics of the small group velocity were described by electric field distribution. Investigating the phase shift, it is confirmed if small group velocity is positive or negative.

Fabrication of a Three-dimensional Terahertz Photonic Crystal Using Monosized Spherical Particles

  • Takagi, Kenta;Seno, Kazunori;Kawasaki, Akira
    • Proceedings of the Korean Powder Metallurgy Institute Conference
    • /
    • 2006.09a
    • /
    • pp.374-375
    • /
    • 2006
  • Three-dimensional artificial crystals with periodicity corresponding to terahertz wave lengths were fabricated by self-assembling monosized metal spherical particles. The metal crystals were weakly sintered to utilize them as templates. The metal templates were inverted to air spheres crystal embedded in dielectric resin though infiltration and etching. The resulting resin inverted crystals clearly presented the photonic stop gaps within terahertz wave region and the frequencies of the gaps were confirmed to agree well with calculation by plane wave expansion method.

  • PDF

Design of a Polarization Splitter Based on a Dual-core Hexagonal-shaped Photonic Crystal Fiber

  • Jegadeesan, Subramani;Dhamodaran, Muneeswaran;Azees, Maria;Murugan, Arunachalam
    • Current Optics and Photonics
    • /
    • v.3 no.4
    • /
    • pp.304-310
    • /
    • 2019
  • In this paper, a microstructured, hexagonal-shaped dual-core photonic crystal fiber (PCF) is proposed. The proposed structure has specific optical properties to obtain high birefringence and short coupling length, for different values of structural parameters varied over a wide range of wavelength. The properties are analyzed using a solid core of silica material. The proposed structure is implemented as a polarization splitter with splitting length of 1.9 mm and a splitting ratio of -34.988 dB, at a wavelength of 1550 nm. The obtained bandwidth in one band gap of about 81 nm. The numerical analysis ensures that the performance of the proposed polarization splitter is better than that of existing ones.

Properties of zero group velocity in 2-Dimensional photonic crystal (2 차원 광결정의 군속도의 특징)

  • Kim, Kyoung-Rae;Hong, Chin-Soo;Lee, Myoung-Rae;Shin, Won-Jin
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
    • /
    • 2009.04a
    • /
    • pp.52-54
    • /
    • 2009
  • A plane wave expansion method(PWEM) was applied for photonic band structure calculation. We examined zero group velocity modes in photonic crystals. The zero group velocity was obtained in second band along G-K direction. We expanded Brillouin zone, and investigated on zero group velocity.

  • PDF

Fabrication of Polymer Laser Device by Two-Photon Induced Photopolymerization Technique

  • Yokoyama, Shiyoshi;Nakahama, Tatsuo;Miki, Hideki
    • Proceedings of the Polymer Society of Korea Conference
    • /
    • 2006.10a
    • /
    • pp.231-231
    • /
    • 2006
  • We fabricated a polymer sub-microstructure for optical device application by two-photon-induced laser lithography technique. Polymer pattern could be minimized as small as ${\sim}100\;nm$. The photopolymerization resin contains laser-dye, thus promising a high level of the optical gain. We utilized the lithography technique to the photonic crystal application, where the template of the two-dimensional photonic crystal was modified by polymer gain medium as defect-shape and line-shape orientations. Photonic band gap effect from polymer-doped photonic crystals is expected to exploit the application such as organic solid-state laser device.

  • PDF

New Phosphor and Material Structures for Displays

  • Summers, Christopher J.;King, Jeffrey;Park, Woun-Jhang
    • 한국정보디스플레이학회:학술대회논문집
    • /
    • 2002.08a
    • /
    • pp.243-252
    • /
    • 2002
  • We propose a new concept: that of photonic crystal phosphors (PCPs) for display and phosphor related applications. It is well known that microcavities with dimensions comparable to the emitting wavelength strongly enhance light-matter interactions, resulting in a significant increase in spontaneous emission rate, which can be directly translated into enhancement in phosphor efficiency. In recent simulations we have demonstrated that when a microcavity is formed in a nano-phosphor structure, the luminescence band is modified, and can be made spectrally sharp and tunable by engineering the geometry/material properties of the cavity and the surrounding photonic crystal lattice. New phosphor material structures based on photonic crystals are proposed. Applications to thin film EL phosphors and particle phosphors are discussed. Additionally, economic methods of synthesizing and incorporating PCPs into current display applications are proposed.

  • PDF

Two-Dimensional Photonic Bandgap Nanolasers (2차원 광밴드갭 나노레이저)

  • Lee, Y. H.;Hwang, J-K;H.Y. Ryu;Park, H. K.;D. J. Shin
    • Proceedings of the Optical Society of Korea Conference
    • /
    • 2001.02a
    • /
    • pp.2-3
    • /
    • 2001
  • Characteristics of two-dimensional slab photonic crystal lasers will be summarized. Room temperature c.w operation is demonstrated at 1.6 $\mu\textrm{m}$ by using InGaAsP slab-waveguide triangular photonic crystal on top of wet-oxidized aluminum oxide. Recently, 2-D PBG structures have attracted a great deal of attention due to their simplicity in fabrication and theoretical study as compared to the three-dimensional counterparts [1]. Air-guided 2-D slab PBG lasers were reported by Caltech group (2). However, this air-slab structure is mechanically fragile and thermally unforgiving. Therefore, a new structure that can remove this thermal limitation is dearly sought after for 2-D PBG laser to have practical meaning. In this talk, we report room-temperature continuous operation of 2-D photonic bandgap lasers that are thermally and mechanically stable.(omitted)

  • PDF

Photonic Crystal Based Bandpass Filter Design for WDM Communication Systems (WDM 시스템에 적합한 광결정 대역 통과 필터 설계)

  • Park, Dong-Soo;Kim, Sang-In;Park, Ik-Mo;Lim, Han-Jo
    • Korean Journal of Optics and Photonics
    • /
    • v.16 no.3
    • /
    • pp.266-274
    • /
    • 2005
  • We have designed photonic crystal based bandpass filters whose characteristics are suitable for WDM communication system. The filters consist of coupled point defect resonators in two-dimensional photonic crystal. The frequency response of coupled resonators has been analyzed by the coupling of modes in time, from which the design parameters for the coupled resonator filters have been extracted. For the appropriate choice of the design parameters, each resonator is treated as a lumped L-C resonance circuit, and from the analogy between the equivalent circuit and the standard L-C filter circuits, the design parameters are simply determined from the table for general filter circuit design. Based on the determined design parameters, a photonic crystal based filter has been designed and its performance has been calculated using the finite-difference time-domain method. The designed filter shows a pass band of 50GHz and 0.5 dB in-band ripple, which is suitable for typical WDM communication systems with 100GHz channel spacing.