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141.
In this paper, a new type of resonant Brewster filters (RBF) with surface relief structure for the multiple channels is first presented by using the rigorous coupled-wave analysis and the S-matrix method. By tuning the depth of homogeneous layer which is under the surface relief structure, the multiple channels phenomenon is obtained. Long range, extremely low sidebands and multiple channels are found when the RBF with surface relief structure is illuminated with Transverse Magnetic incident polarization light near the Brewster angle calculated with the effective media theory of sub wavelength grating. Moreover, the wavelengths of RBF with surface relief structure can be easily shifted by changing the depth of homogeneous layer while its optical properties such as low sideband reflection and narrow band are not spoiled when the depth is changed. Furthermore, the variation of the grating thickness does not effectively change the resonant wavelength of RBF, but have a remarkable effect on its line width, which is very useful for designing such filters with different line widths at desired wavelength. 相似文献
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采用传输矩阵分析法、数值模拟和实验研究相结合的方法研究了由光耦合器(OC)、偏振控制器(PC)和保偏光纤(PMF)组成的高双折射Sagnac干涉环的透射特性。理论分析了PMF特性和PC状态对输出特性的影响,并通过数值模拟得到了PMF长度、双折射率(Δn)和PC状态不同时所对应的透射光谱。最后通过实验验证得出了波长间隔只由PMF的长度和双折射率Δn决定,透射率大小只由PC状态决定,而透射谱的峰值位置由PMF和PC状态共同决定的规律。实验结果与理论分析结果非常一致,对Sagnac环透射规律的研究对这种可调谐滤波器在多波长光纤激光器中的应用具有一定的参考价值。 相似文献
146.
Semiconductor-Optical-Amplifier-Based Inverted and Non-Inverted Wavelength Conversion at 40 Gb/s Using a Detuning Optical Bandpass Filter 下载免费PDF全文
We experimentally demonstrate 40Gb/s semiconductor-optical-amplifier-based tunable wavelength conversion (WC) using a detuning optical bandpass filter. Both inverted and non-inverted WCs are obtained by shifting the filter central wavelength with respect to the probe wavelength. When the filter is red shifted by 0.4nm or blue shifted by 0.3nm, the WC is non-inverted. However, when the filter is blue shifted by 0.1 nm, the WC is inverted. It is experimentally demonstrated that the WC has a tunable range covering the C-band. 相似文献
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Structural and Optical Properties of Zinc Nitride Films Prepared by Pulsed Filtered Cathodic Vacuum Arc Deposition 下载免费PDF全文
SENADIM TUZEMEN Ebru KAVAK Hamide ESEN Ramazan 《中国物理快报》2007,24(12):3477-3480
Polycrystalline zinc nitride films are deposited on Coming 7059 glass substrates by pulsed filtered cathodic vacuum arc deposition (PFCVAD). The crystallographic structure is studied by means of x-ray diffraction. These measurements show that all the films are crystallized in the cubic structure, in a preferred orientation along the (332) and (631) directions. Weak XRD signal shows small crystallites distributed in an amorphous tissue. A small improvement of crystallinity is observed with annealing. Optical parameters such as absorption, energy band gap, Urbach tail, extinction coefficients have been determined. The Urbach tail energy is decreased with annealing at 500℃ for one hour. Energy band gap values are found to be increased by annealing. 相似文献
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