Photonic crystal

About: Photonic crystal is a research topic. Over the lifetime, 43424 publications have been published within this topic receiving 887083 citations.

Quasi-amorphous colloidal structures for electrically tunable full-color photonic pixels with angle-independency.

Abstract: Similar to other PBG materials prepared by self-assembly of block copolymers or by lithographic techniques, colloidal photonic crystals require crystalline or highly ordered periodic structures to exhibit PBG by the collective refraction in longrange. [ 9–11 ] In this case, the PBG can be tuned by modulation of periodicity or/and refractive index contrast. [ 9 , 12 ] While such tunable photonic crystals based on crystalline structures have recently been proposed as active components of display [ 13–16 ]

Quantitative Measurement of Transmission, Reflection, and Diffraction of Two-Dimensional Photonic Band Gap Structures at Near-Infrared Wavelengths

Abstract: We present quantitative measurements of the interaction between a guided optical wave and a two-dimensional photonic crystal using spontaneous emission of the material as an internal point source. This is the first analysis at near-infrared wavelengths where transmission, reflection, and inplane diffraction are quantified at the same time. Low transmission coincides with high reflection or in-plane diffraction, indicating that the light remains guided upon interaction. Also, good qualitative agreement is found with a two-dimensional simulation based on the transfer matrix method. [S0031-9007(97)04591-2]

Design of optomechanical cavities and waveguides on a simultaneous bandgap phononic-photonic crystal slab

Abstract: In this paper we study and design quasi-2D optomechanical crystals, waveguides, and resonant cavities formed from patterned slabs. Two-dimensional periodicity allows for in-plane pseudo-bandgaps in frequency where resonant optical and mechanical excitations localized to the slab are forbidden. By tailoring the unit cell geometry, we show that it is possible to have a slab crystal with simultaneous optical and mechanical pseudo-bandgaps, and for which optical waveguiding is not compromised. We then use these crystals to design optomechanical cavities in which strongly interacting, co-localized photonic-phononic resonances occur. A resonant cavity structure formed by perturbing a “linear defect” waveguide of optical and acoustic waves in a silicon optomechanical crystal slab is shown to support an optical resonance at wavelength λ0 ≈ 1.5 µm and a mechanical resonance of frequency ωm/2π ≈ 9.5 GHz. These resonances, due to the simultaneous pseudo-bandgap of the waveguide structure, are simulated to have optical and mechanical radiation-limited Q-factors greater than 107. The optomechanical coupling of the optical and acoustic resonances in this cavity due to radiation pressure is also studied, with a quantum conversion rate, corresponding to the scattering rate of a single cavity photon via a single cavity phonon, calculated to be g/2π = 292 kHz.

Structural tuning of guiding modes of line-defect waveguides of silicon-on-insulator photonic crystal slabs

Abstract: We experimentally demonstrate the structural tuning of the waveguiding modes of line defects in photonic crystal (PC) slabs. By tuning the defect widths, we realized efficient single-mode waveguides that operate within photonic band gap frequencies in silicon-on-insulator PC slabs. The observed waveguiding characteristics agree very well with three-dimensional finite difference time-domain calculations. We also directly measured the propagation loss of the line defect waveguides and obtained a value of 6 dB/mm.