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1.
S.S. Mishra 《Optik》2011,122(8):687-690
A highly non-linear hollow core photonic crystal fiber (PCF) having three ring-hexagonal structure is designed. The full vector finite element method with perfectly matched layer is used to investigate the non-linear properties of hollow core PCF effectively. The effective area of modal pattern is also studied for the same newly designed structure. It is found that when effective area is very small the non-linearity is very high. 相似文献
2.
Effect of interstitial air holes on Bragg gratings in photonic crystal fibre with a Ge-doped core 下载免费PDF全文
The effect of interstitial air holes on Bragg gratings in photonic
crystal fibre (PCF) with a Ge-doped core is numerically investigated
by using the beam propagation method (BPM). It is shown that the
interstitial air holes (IAHs) can make Bragg resonance wavelength
λB shift a little towards short wavelengths and
increase λB-λ1 (the wavelength spacing
between the main peak with Bragg resonance wavelength λB and the first side peak with wavelength λ1 and the
coupling coefficient к of Bragg resonance. Moreover, when
the ratio of air hole diameter (d) to pitch (Λ),
d/Λ, is small, IAHs can suppress the cladding mode
resonance. When d/Λ is large, IAHs increase the number
of mode that could strongly interact with the fundamental mode. By
comparing the transmission spectral characteristics of PCF-based
fibre Bragg grating (FBG) with IAHs with those without IAHs at the
same air-filling fraction, it is clarified that the change of
transmission spectral characteristics of PCF-based FBG with IAHs is
not due to a simple change in air-filling fraction. It is also
closely related to the distribution of interstitial air holes. 相似文献
3.
4.
Broad and ultra-flattened supercontinuum generation in the visible wavelengths based on the fundamental mode of photonic crystal fibre with central holes 下载免费PDF全文
By coupling a train of femtosecond pulses with 100 fs pulse width at a repetition rate of 76 MHz generated by a mode-locked Ti:sapphire laser into the fundamental mode of photonic crystal fibre(PCF) with central holes fabricated through extracting air from the central hole,the broad and ultra-flattened supercontinuum(SC) in the visible wavelengths is generated.When the fundamental mode experiences an anomalous dispersion regime,three phases in the SC generation process are primarily presented.The SC generation(SCG) in the wavelength range from 470 nm to 805 nm does not emerge significant ripples due to a higher pump peak power and the corresponding mode fields at different wavelengths are observed using Bragg gratings.The relative intensity fluctuations of output spectrum in the wavelength ranges of 530 nm to 640 nm and 543 nm to 590 nm are only 0.028 and 0.0071,respectively. 相似文献
5.
研究了光波在没有光子带隙的三角晶格型光子晶体多模波导中的传播特性. 利用等效折射率法,将该结构等效为三层平板介质波导,基于自映像原理,数值分析和模拟了其多模干涉效应. 研究结果表明,由于全内反射和分布式布拉格反射的联合效应,光场类似于传统波导模式,能高效地传输;随着填充率的增大,高透射区域将向波长减小的方向移动,带宽和透射率也随之增加, 研究结果为实际应用中选择适当的填充率提供了理论依据.
关键词:
光子晶体多模波导
全内反射
填充率
时域有限差分法 相似文献