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It is shown that superprism effect can be observed not only in 2D and 3D photonic crystal but also in 1D photonic crystal. To observe the effect a diffraction grating should be put on the top of the 1D PC. It is shown that the band gap more dramatically appears in 1D PC than in 2D PC. This effect makes all PBG effects including superprism effect more pronounced and also weakens the influence of losses. 相似文献
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Adam Rudziński Anna Tyszka-Zawadzka Paweł Szczepański 《Optical and Quantum Electronics》2007,39(4-6):501-510
The aim of this paper is to present the analysis of influence of defects in 1D photonic crystal (PC) on the density of states
and simultaneously spontaneous emission, in both spatial and frequency domains. In our investigations we use an analytic model
of 1D PC with defects. Our analysis reveals how presence of a defect causes a defect mode to appear. We show that a defect
in 1D PC has local character, being negligible in regions of PC situated far from the defected elementary cell. We also analyze
the effect of multiple defects, which lead to photonic band gap splitting. 相似文献
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We theoretically studied a left-hand structure based on a two-dimensional (2D) photonic crystal (PC)with a negative refractive index. The propagation of electromagnetic waves in the proposed PC structure is investigated through dispersion characteristic analysis and numerical simulation of field pattern. The designed PC structure can exhibit all angle negative refraction, and the corresponding effective refractive indices along all directions are almost same and close to the ideal value of -1. A flat lens formed from such a PC has been designed and its imaging properties have been investigated systematically. 相似文献
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Bogaerts Wim Bienstman Peter Taillaert Dirk Baets Roel De Zutter Daniel 《Optical and Quantum Electronics》2002,34(1-3):195-203
We present a detailed study of out-of-plane scattering losses in a 1D approximation of 2D photonic crystal slabs. In 2D photonic crystals with a waveguide structure in the third dimension, the periodic structure (in a lot of applications a 2D arrangement of holes etched through the core and cladding) will cause light to scatter out of the waveguide plane. We studied the out-of-plane scattering losses of these holes using a 2D approximation of this 3D structure, with etched slots instead of holes. Our simulation techniques included mode expansion with PML and FDTD. We will present the influence of the refractive index contrast between core and cladding of the layered structure. We show that the losses increase with higher index contrast between core and cladding, but that with very high index contrasts and under the right circumstances light can be coupled into lossless Bloch modes. 相似文献
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Nanofluidic tuning of photonic crystal circuits 总被引:1,自引:0,他引:1
By integrating soft-lithography-based nanofluidics with silicon nanophotonics, we demonstrate dynamic, liquid-based addressing and high deltan/n (approximately 0.1) refractive index modulation of individual features within photonic structures at subwavelength length scales. We show ultracompact tunable spectral filtering through nanofluidic targeting of a single row of holes within a planar photonic crystal. We accomplished this with an optofluidic integration architecture comprising a nanophotonic layer, a nanofluidic delivery structure, and a microfluidic control engine. Variants of this technique could enable dynamic reconfiguration of photonic circuits, selective introduction of optical nonlinearities, or delivery of single molecules into resonant cavities for biodetection. 相似文献
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The electromagnetic field in subwavelength resonant diffractive optical elements is so concentrated that a very shallow surface corrugation obtained by wet chemical micro–nano-etching is sufficient to give rise to high contrast diffraction effects allowing a high wavelength-, polarization- or transverse-mode-selectivity which is not achievable by conventional diffractive elements. Two examples of polarizing laser mirrors at both extremes of the optical spectrum with wet-etched grating bypassing and cutting through the 1D photonic crystal are demonstrated. 相似文献
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Although the investigation on photonic band gap materials has been done more than two decades, it is still a big challenge to fabricate three-dimensional photonic crystal (PC) possessing wide band gaps in visible range. In this article, we have reviewed recent progresses on fabricating the PC with low refractive index material in visible range. In contrast to the material with large refractive index, it is cheap to use low refractive index material in fabricating the PC and will be greatly beneficial for future industrial productions. The holographic method to fabricate such a PC has been introduced, applying it to the design of the microlaser has also been discussed. 相似文献
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正负折射率交替一维光子晶体窄带梳状滤波器 总被引:3,自引:1,他引:2
利用传输矩阵法计算了正负折射率交替一维光子晶体的带隙特性。结果表明这种光子晶体具有宽而平坦的禁带,窄而尖锐的通带。这种带隙特性是受到布拉格散射、法布里-珀罗谐振和n-=0禁带共同影响的结果,通带位置决定于法布里-珀罗谐振。在理论分析基础上设计出密集波分复用用窄带梳状滤波器,给出信道间隔为0.8nm的梳状滤波器的仿真结果。仿真结果表明这种梳状滤波器具有信道间隔窄、禁带平坦、通带极窄的特点。信道间隔可以通过改变一维光子晶体单元周期光学厚度调节。 相似文献
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Photonic Jet by a Near‐Unity‐Refractive‐Index Sphere on a Dielectric Substrate with High Index Contrast
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Liyang Yue Bing Yan James N. Monks Rakesh Dhama Zengbo Wang Oleg V. Minin Igor V. Minin 《Annalen der Physik》2018,530(6)
Photonic jets are normally generated in transmission mode and are represented as a spatially localized high‐intensity region on the shadow side of a particle‐lens, with a background to medium refractive index contrast of 1.3–1.7 while illuminated by a plane wave. Here, a photonic jet is discovered in the opposing plane wave propagation direction and lies in the area in the upper boundary of a near‐unity refractive index sphere on a high refractive index dielectric substrate. The redistribution of the power flow is inhibited during the reflected wave passing the near‐unity refractive index sphere. This has led to a unique effect on the focus position and shape of the produced photonic jet in reflection mode which can be maximally maintained near the sphere regardless of the modulation of the refractive index for the dielectric substrate material. 相似文献
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2D triangular photonic crystals (PCs) have been integrated as laser mirrors in electrically pumped InGaAs/AlGaAs ridge waveguide lasers. The investigated PC lattice constants range from 160 to 400 nm with light incident along both main symmetry directions M and K. The observed cw laser performance is strongly dependent on both orientation and period of the PC. This behaviour is discussed using a 2D transfer matrix calculation of the PC reflectivity. As a demonstrator device relying on the 2D light confining properties of the PC, an active beamsplitter with a bending radius of 5 m is presented. Here, the PC is successfully used as cladding material in the S-bent regions of the ridge waveguide, significantly reducing the bending loss. 相似文献
16.
Although the investigation on photonic band gap materials has been done more than two decades, it is still a big challenge
to fabricate three-dimensional photonic crystal (PC) possessing wide band gaps in visible range. In this article, we have
reviewed recent progresses on fabricating the PC with low refractive index material in visible range. In contrast to the material
with large refractive index, it is cheap to use low refractive index material in fabricating the PC and will be greatly beneficial
for future industrial productions. The holographic method to fabricate such a PC has been introduced, applying it to the design
of the microlaser has also been discussed. 相似文献
17.
Edilson A. Camargo Harold M.H. Chong Richard M. De La Rue 《Photonics and Nanostructures》2004,2(3):207-213
We have fabricated and measured a four-port coupled channel-waveguide device using W1 channel waveguides oriented along ΓK directions in a two-dimensional (2D) hole-based planar photonic crystal (PhC) based on silicon-on-insulator (SOI) waveguide material, at operation wavelengths around 1550 nm. 2D FDTD simulations and experimental results are shown and compared. The structure has been designed using a mode conversion approach, combined with coupled-mode concepts. The overall length of the photonic crystal structure is typically about 39 μm and the structure has been fabricated using a combination of direct-write electron-beam lithography (EBL) and dry-etch processing. Devices were measured using a tunable laser with end-fire coupling into the planar structure. 相似文献
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《Superlattices and Microstructures》1997,22(3):393-397
The symmetry and orientation of a photonic lattice of 3D ordered porous silica matrices (synthetic opals) are determined by analysis of transmission electron micrographs. By optical transmission measurements the photonic band edges are mapped out at pointsLandKof the Brillouin zone. It is shown that modulating the refractive index of opal pores by filling them with liquids results in variation of the light attenuation length within the forbidden gap. To increase the refractive index contrast of the lattice, the pores of opals were filled with CdS. A dramatic decrease in attenuation length is observed for opal/CdS. The parameters of a photonic lattice with a ‘pseudo-gap’, that is, with a prominent depletion of the photonic density of states, are estimated. 相似文献
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Transmission characteristics of one-dimensional (1D) photonic crystals (PCs) heterostructures containing defective are studied using the transfer matrix method. The key is to search the best combination style for different 1D PCs to form heterostructures. It is shown that the non-transmission range over near ultraviolet and visible range can be substantially enlarged and the phenomenon of narrow band PC filter in near ultraviolet can be realized by adjusting the repeat cycle counts of various photonic crystals. The theoretical results on multiple heterostructures containing TiO2/SiO2 multilayer films are presented. With a perfect omni-directional and high peak transmission filters for TE modes, this structure opens a promising way to fabricate ultra-narrow band PC filters with wide non-transmission range in near ultraviolet and visible range. 相似文献
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运用Bloch定理和传输矩阵方法,研究了与色散介质毗邻的由两种材料组成的半无限一维光子晶体局域表面态的电场和色散关系.和以空气为背景的一维光子晶体相比,毗邻色散介质的光子晶体表面模色散曲线在一定堆积次序下会在较低的带隙中发生断开,较高带隙中的表面模群速度在不同堆积次序下会有很大差异.当与色散介质毗邻的物质折射率较大时,较高带隙中的表面模群速度较小;与色散介质毗邻的物质折射率较小时,较高带隙中表面模的群速度较大. 相似文献