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1.
提出并实验研究了一种基于铌酸锂薄膜光波导的电光调谐的光栅辅助定向耦合器。该耦合器由单模与双模脊形波导及制作于双模波导侧壁的长周期光栅构成。长周期光栅的引入补偿了单模与双模波导中基模的相位失配,可在共振波长实现两波导中基模的高效耦合。进一步地,在双模脊形波导两侧制作调谐电极实现了高速、低驱动电压的电光调谐功能。优化了器件的制作工艺,并采用单次干法刻蚀将耦合器的光栅与波导同步制作于X切铌酸锂薄膜上。测试结果表明所制作的器件在1 595.3 nm波长处实现了14.8 dB的隔离度,其电光调谐效率为0.38 nm/V(1 595.3 nm~1 599.0 nm),热光调谐效率为0.14 nm/℃(25℃~50℃)。该器件可用于实现可调谐滤波、滤模、电光调制及高灵敏度温度传感等功能。  相似文献   

2.
设计了一种基于LiNbO_3的长周期波导光栅可调谐耦合器.该耦合器利用长周期光栅的独有特性将输入波导的导模经包层模耦合至输出波导导模.由于LiNbO_3的电光效应,波导光栅芯层与包层的有效折射率随外加电压变化,从而耦合器的谐振波长及耦合效率可由外加电压调谐.分析了光栅周期与耦合器的长度对耦合器带宽和耦合效率调谐范围的影响,以及波导尺寸对谐振波长调谐灵敏度的影响.结果表明光栅周期越短,耦合器长度越长,则耦合器的带宽越窄,耦合效率调谐范围也越大.此外,谐振波长调谐灵敏度随波导宽度的增加而减小,而波导厚度对谐振波长调谐灵敏度的影响可以忽略.对光栅周期为94μm、长度为3.52cm的耦合器进行仿真,结果表明,谐振波长灵敏度为26.2pm/V,3dB带宽可达4.5nm,当外加电压从0变化到200V时,谐振波长变化5.24nm,耦合效率可在1到0.15之间进行调谐.  相似文献   

3.
刘群 《光子学报》2013,42(1):90-93
基于双折射铌酸锂晶体的电光效应,设计了一种偏振无关的二端口波导型多波长可调谐滤波器.在非对称干涉仪的上下分支波导上,耦合电极与相移电极周期性交叉级联实现模式的偏振转换.利用琼斯矩阵的Z域分析,求解驱动电压模拟实现多个波长的同时选择.仿真实现了自由光谱范围内分布任意的窄带多波长输出.波长中心处传输率为100%;旁瓣大小受到所选波长个数的影响,三个波长同时滤波的旁瓣可达12 dB.同时得到了梳状滤波输出谱,其通带顶部平坦,旁瓣可达15 dB以上.  相似文献   

4.
本文利用一维耦合腔光子晶体,提出了一种声光可调谐平顶滤波器.该滤波器利用声光效应,通过改变超声波频率使一维耦合腔光子晶体透射谱的平顶滤波器的中心波长产生漂移,从而实现可调谐的滤波功能.基于传输矩阵法和声光效应理论,建立了这种平顶滤波器的理论模型;利用COMSOL软件,对平顶滤波器的矩形度、通带带宽、插入损耗、可调谐特性、加工精度进行仿真研究.研究结果表明,通过施加频率为6-11 MHz的超声波,可实现通带带宽为5-6 nm及中心波长在1514-1562 nm范围内可调谐的平顶滤波器;在可调谐范围内通带带宽内插入损耗不超过2.23 dB,最低仅为0.78 dB,矩形度最低可达1.4;加工误差在±10 nm内平顶滤波器的中心波长、矩形度、插入损耗、通带带宽出现的偏差很小.该平顶滤波器具有易于设计和集成、通带平坦、可调谐范围宽、通带带宽稳定、插入损耗低、品质因素高的特点,在光开关、可调谐光纤激光器、光纤传感等光通信领域有重要应用.  相似文献   

5.
全光缓存器是未来全光网络中不可或缺的关键器件.针对可控光延迟和光存储的应用需求,研究了光子晶体波导中慢光传输的外部动态调制.设计了一种新型的聚合物光子晶体波导结构.用平面波展开法仿真得到该波导结构带隙中存在单一的TE导模,导模带边处的群速度可达10-2c.由于基底聚合物材料具有高电光系数和瞬态的电光响应时间,且导模慢光传输产生的电磁场局域对电光效应有增强作用.可在低涮制电压的条件下实现对慢光导模的大范围动态调制.数值分析得到在外加调制电压为80 V时导模带边波长的移动幅度达80.8 nm.慢光导模的移动随调制电压的变化基本呈线性关系,且调制的灵敏度约为1 nm/V.这种线性的外部动态调制基本可满足全光网络对慢光光缓存的需求.  相似文献   

6.
带虚设层的抗反射结构导模共振滤波器设计与分析   总被引:1,自引:0,他引:1       下载免费PDF全文
桑田  蔡托  刘芳  蔡绍洪  张大伟 《物理学报》2013,62(2):24215-024215
提出带虚设层的抗反射导模共振滤波器结构及设计方法,该方法适用于任意角度入射带虚设层的抗反射结构导模共振滤波器设计与分析.得到带虚设层的导模共振滤波器抗反射结构所满足的关系式.指出在维持虚设层光学厚度不变的情况下,可以通过不同选材,在低反射旁带中实现等带宽不同波长的选择.此外,由于结构的抗反射特性在低角范围内具有较大的角度容差,改变入射角,可以实现滤波波长及光谱带宽在宽光谱范围内的准线性可调谐.  相似文献   

7.
刘晓  周骏  朱本强  金理 《光子学报》2011,40(11):1723-1727
本文构建了含有电光材料LiNbO3的一维对称广义Fibonacci光子晶体结构,提出并设计了一种基于该结构的可调谐滤波器,并利用传输矩阵法对设计的滤波器的可调谐滤波特性进行了理论研究.数据模拟结果表明:保持对称广义Fibonacci光子晶体的几何结构不变,通过改变电极所在处施加在电光介质(LiNbO3)层上的外加电场,...  相似文献   

8.
刘晓  周骏  朱本强  金理 《光子学报》2014,40(11):1723-1727
本文构建了含有电光材料LiNbO3的一维对称广义Fibonacci光子晶体结构,提出并设计了一种基于该结构的可调谐滤波器,并利用传输矩阵法对设计的滤波器的可调谐滤波特性进行了理论研究.数据模拟结果表明:保持对称广义Fibonacci光子晶体的几何结构不变,通过改变电极所在处施加在电光介质(LiNbO3)层上的外加电场,即可实现滤波器的滤波通道波长的调节,滤波通道波长的改变与外加电压呈线性关系,随着外加电压的增加,滤波通道波长向短波长方向移动.此外,电压一定时,通道波长随光的入射角的增加向短波长方向移动;光的入射角一定时,外加正电压下,通道波长随电压增加发生蓝移,而外加负电压下,通道波长随反向电压的增加发生红移.最后,讨论了双电场作用下的多通道波长滤波器的结构极其特性.以上结果对于新型光子晶体器件的设计具有重要的参考价值.  相似文献   

9.
石俊凯  王国名  黎尧  高书苑  刘立拓  周维虎 《物理学报》2019,68(6):64206-064206
构建了基于损耗非对称非线性光学环镜的8字腔掺铒光纤锁模激光器,并讨论了腔内滤波带宽对腔内脉冲演化和激光器输出特性的影响.在非线性光学环镜中引入双向输出耦合器,耦合器和传输光纤位置的不对称产生非互易性,实现锁模运转.利用自制的可调谐滤波器实验研究了滤波带宽对激光器的影响.当滤波带宽为2.1 nm时,腔内脉冲的演化过程受滤波和孤子效应的共同作用,激光器顺时针和逆时针输出脉冲半高全宽分别为583.7fs和2.94 ps.随着滤波带宽增大,滤波的作用逐渐减弱,激光器两路输出脉冲参数逐渐接近,并接近傅里叶变换极限脉冲.当滤波带宽较大时,腔内脉冲的演化过程受增益谱和孤子效应的共同作用,激光器顺时针和逆时针输出脉冲均为变换极限脉冲,半高全宽约为440 fs.通过调节滤波器中心波长实现了对激光器输出脉冲光谱的连续调谐,调节范围大于30 nm.  相似文献   

10.
铁电液晶缺陷光子晶体调谐滤波器的设计   总被引:2,自引:0,他引:2  
钱祥忠 《光子学报》2007,36(3):425-428
将铁电液晶作为缺陷层引入一维光子晶体中,用电场改变液晶分子的取向,形成光子晶体快速可调谐滤波器.用传输矩阵法研究了铁电液晶缺陷光子晶体的可调谐滤波特性,计算了电压和液晶材料参量对滤波器透射谱的影响.结果表明:改变电压能容易改变光子晶体滤波器透射峰的位置、强度、个数和带宽,实现良好的调谐滤波功能.  相似文献   

11.
A tunable Fabry-Perot (F-P) filter by using electro-optic polymer film is proposed. The electro-optic polymer is alkoxysilane dye (ASD)/SiO2-TiO2 hybrid material, whose electro-optic coefficient γ33 is about 5 pm/V. The wavelength tuning range of 3.8 nm under 400-V DC voltage and the nonlinear characteristic with the electric field have been obtained via electro-optical properties of polymer. Both of polymer film fabrication and F-P filter design have been introduced. The tunable F-P filter is designed for the application of two-input/two-output port wavelength-selective optical switch. Also, some problems have been discussed in this letter.  相似文献   

12.
利奥型可调谐液晶电光滤波器的特性分析   总被引:11,自引:3,他引:8  
根据液晶的电光效应和利奥滤波器的原理设计了利奥型液晶电光调谐滤波器,并且从理论上和实验上证明了其可行性;为了克服其在红外波段的缺点,设计了法布里-珀罗腔液晶可调谐滤波器,并且给出了理论模拟。理论模拟证明法布里-珀罗腔液晶可调谐滤波器具有调谐范围大、带宽窄的优点。  相似文献   

13.
An electrically tunable optical filter with ultra-fast tuning time of a few picoseconds is proposed and demonstrated. The filter consists of a phase modulator with HiBi pigtails sandwiched between two polarizers. Tuning of 6.62 nm for a 16.06 nm FSR filter is obtained with an applied voltage of 0.9 V. Tuning speed at 10 Gb/s and risetime of 40 ps is demonstrated with a frequency shift keying modulation experimental setup. Faster tuning speed is potential since the scheme is based on the electro-optic effect of the LiNO3 crystal with sub-picosecond response time.  相似文献   

14.
A novel scheme of tunable optical comb filter constructed by cascading a polarization-swapping MZI and a phase modulating Sagnac loop is proposed. The key features of this comb filter design are its polarization-independence and high speed in wavelength tuning. The wavelength tunability can be readily achieved by incorporating an electro-optic phase modulator into the Sagnac loop. In addition, the filter can be made amplitude adjustable as well. The filter will be desirable for multi-wavelength fiber lasers, multi-channel optical signal processing and optical WDM systems.  相似文献   

15.
We have measured the intensity fluctuations of the second-harmonic mode generated in a MgO:LiNbO3 external monolithic cavity pumped by a Nd:YAG laser. The cavity has mirror coatings for both the fundamental and the second-harmonic mode. We scan the cavity using the electro-optic effect of the crystal and observe that the second-harmonic beam of 2 mW exhibits a quantum noise reduction of 40(±5)%. In addition, we report on the active frequency stabilization of the monolithic device used in our squeezing experiments. Several fast tuning parameters such as the electro-optic effect, the photo-elastic effect, and the laser frequency have been investigated. With these tuning parameters the monolithic resonator can be locked on double-resonance at the phase-matching temperature, which is a prerequisit for observing squeezing in a cw-regime.  相似文献   

16.
We theoretically investigated a digitally tunable laser with a chirped ladder filter and a ring resonator to obtain a wide wavelength tuning range covering the whole C- or L- band. The clear relation between the tuning range and laser structure, especially the ladder filter, is described analytically. The introduction of a chirped structure into a ladder filter is effective in achieving both wide tunability and a stable lasing mode. A numerical simulation based on multimode rate equations shows that a tuning range of over 40 nm and a mode suppression ratio over 40 dB can be achieved by introducing a chirped ladder filter.  相似文献   

17.
Nearly bandwidth-limited, time-synchronized, frequency tunable picosecond pulses are generated in an active and passive mode-locked laser consisting of an Nd: silicate glass and an Nd: phosphate glass branch and a common antiresonant ring. An electro-optic Q-switch, an acousto-optic modulator and a saturable absorber in the antiresonant ring are responsible for mode locking and time synchronization. Three-plate birefringent filters in the gain branches are used for spectral narrowing (pulse duration broadening) and wavelength tuning. Pulses of 40 ps duration with a synchronization jitter of 10 ps are generated. A frequency tuning range from 0 to 350 cm-1 is achieved.  相似文献   

18.
介绍一种实时声光图像相关器。在该系统中,一个声光偏转器和一个激光二极管阵列分别被用作输人图像和滤波器的电光转换器件。二维相关由工作于时间延迟积分模式下的一个二维CCD探测器完成。最后描述这种相关器在模式识别中的应用。  相似文献   

19.
An electro-optic polarization converter with programmable spectral output produced on lithium niobate at the 1530 nm wavelength regime is reported. Programmability is achieved by applying spatially periodic weighted voltages on interdigital electrode sets to independently adjust the coupling coefficients, and is controlled electronically via a personal computer interface. The operation of a device with 16 electrode sets as a programmable tunable wavelength filter is demonstrated. The number of selectable channels depends on the number of electrode sets. A 3-dB bandwidth ∼1 nm and a tuning range of 10 nm are measured. Nearest side lobes ?18 dB below the main peak are realized with apodization.  相似文献   

20.
Wang TJ  Chu CH  Lin CY 《Optics letters》2007,32(19):2777-2779
Electro-optical tuning of a microring resonator fabricated on lithium niobate (LiNbO3) is presented. The device structure, including microring resonator and couplers, is designed in detail and is produced by titanium diffusion on the wet-etched LiNbO3 ridge surface. The resonance wavelengths for TM and TE polarizations can be tuned by electro-optic effect. The output characteristics of through port and drop port in the microring resonators are measured, and the effect of applied voltage on the shift of resonant wavelength is discussed. The presented microring resonators have the features of fast tuning speed, high material stability, bidirection wavelength shift, and no heating interference. Realization of such a microring resonator on LiNbO3 makes the utilization of electro-optic tuning and nonlinear effects in the versatile photonic applications of microring resonators achievable.  相似文献   

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