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新型长波长InP基谐振腔增强型光探测器 总被引:3,自引:1,他引:3
介绍了一种新型长波长InP基谐振腔增强型(RCE)光探测器。通过V(FeCl3):V(H2O)溶液对InGaAs牺牲层的选择性湿法腐蚀,制备出具有InP/空气隙的高反射率分布布拉格反射镜(DBR),并将该选择性湿法腐蚀技术成功地应用到长波长InP基谐振腔增强型光探测器的制备中去,从而彻底解决了InP/InGaAsP高反射率分布布拉格反射镜难以外延生长的问题。所制备出的谐振腔增强型光探测器,其台面面积为50μm×50μm,底部反射镜为1.5对的InP/空气隙分布布拉格反射镜,顶部反射镜靠InGaAsP与空气的界面反射来实现。测试结果表明,该谐振腔增强型光探测器在波长1.510μm处获得了约59%的峰值量子效率,在3V反偏压下暗电流为2nA,3dB响应带宽达到8GHz。 相似文献
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一种具有亚波长光栅结构的光探测器的设计 总被引:2,自引:0,他引:2
高速智能光纤通信系统和网络的飞速发展对光电探测器提出了更高要求.利用严格耦合波(RCWA)理论,给出了在亚波长光栅(SWG)下方具有分布布拉格反射镜(DBR)结构的理论分析模型,将这种结构作为反射镜应用于谐振腔增强型光探测器(RCE PD)的设计中.仿真表明由于SWG的引入,只需要4对λ/4厚度的InGaAsP/InP系DBR,可使整体膜系结构实现在中心波长1.55 μm处反射率达到99.7%,在1.40 μm至1.62/μm范围内反射率高于99%.引入SWG后的RCE PD在1.55 μm附近的量子效率接近90%,串扰衰减系数与量子效率的乘积超过15 dB.有效地解决了InGaAsP/InP介质膜系DBR作为谐振腔反射镜反射率低、反射带宽窄的问题. 相似文献
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Massachusetts Institute of Technology(MIT)大学的科研人员在光子带隙反射镜研究成果的基础上,开发了一种新型光纤。光子带隙反射镜是一种能反射光的新型介质反射镜,具有低损耗性能。与在一特定波长只反射很窄入射光束的其他介质反射镜不同,这种光子带隙反射镜能在很宽的波段范围内反射各种入射光束,并具有很高的反射率。 相似文献
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半导体光放大器(SOA)能稳定产生高消光比的窄脉冲光,在光纤传感领域得到了广泛应用,但目前大多方案仅采用单向调制的SOA产生脉冲光。为了进一步提高脉冲光的消光比,基于SOA能双向工作的特点提出了一种双向窄脉冲光调制的SOA系统。使用光纤反射镜对SOA单向调制输出的脉冲光进行反射,使反射光重新返回到SOA进行第二次脉冲光调制。实验结果表明:相比单向调制,在低输入功率下,双向调制最大可获得6.18 dB的额外增益;对于输入峰值功率为6 dBm的脉冲光,双向吸收能使泄漏光强度进一步减弱30 dB以上,整体吸收率达到72 dB以上。 相似文献
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针对当前2. 0μm GaSb基垂直腔面发射激光器发展中由于传统的P面分布布拉格反射镜(P-DBRs)带来的高电阻和严重光吸收这一瓶颈问题,采用严格耦合波方法仿真设计了含高对比度亚波长光栅(HCG)的P面反射镜.实验结果表明,这种制备工艺简单的反射镜在2. 0μm中心波长附近,TM波入射时反射率超过99. 5%的高反射带宽为278 nm,反射率99. 9%以上的高反射带宽达到148 nm,完全能够满足VCSEL对谐振腔镜的要求,且能有效避免因异质外延等造成反射镜衍射特性劣化等问题. 相似文献
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Electromagnetic band-gap (EBG) structures have unique properties in controlling the propagation of electromagnetic wave and
have been applied to a wide range of electromagnetic devices design. In this paper, a double-sided printed dipole (DSPD) array
backed by an EBG reflector is proposed for achieving a low-profile design as well as gain enhancement. Simulation results
show that a reduction of more than 55% in antenna height can be obtained by placing the DSPD array over an EBG reflector rather
than a perfect electric conductor (PEC) reflector. And the obtained gain of the antenna with an EBG reflector is about 1.9 dB
higher than that with a PEC reflector at the operating frequency 2.77 GHz. The EBG reflector can be utilized to reduce a cavity-backed
antenna height and enhance the antenna radiation efficiency. The design has a good potential application to antenna arrays
with more elements in wireless communication. 相似文献
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描述了用波纹喇叭中的 HE_(21)模抵消单偏置抛物面天线非对称平面交叉极化分量的基本原理,介绍了 TE_(21) 模激励器、波纹喇叭的设计方法和展宽馈源抑制单偏置天线交叉极化分量频带宽度的设计方法,给出了 C 波段 2.4m 单偏置抛物面天线的实验测试数据,单偏置抛物面天线非对称平面交叉极化电平改善了10dB,抑制交叉极化分量的馈源相对工作频带宽度大于8%。这种 TE_(21)模激励技术和与主模 TE_(11)模相位差的调整方法,对馈源的电压驻波比几乎没有影响。 相似文献
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Tunable single-mode oscillation has been obtained from a 1.3?m multimode laser using a tunable fibre grating reflector in a fibre external cavity. The output was tuned over a 26 nm range with a secondary mode suppression greater than 25 dB at the centre of the gain profile. 相似文献
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An experimental investigation of a novel corner reflector antenna with improved performance is reported. The corner reflector antenna has been structurally modified by attaching two more reflector elements. The parameters such as the primary corner angle, position, width and angle of the secondary elements have significant effects on the H-plane radiation characteristics of the antenna. Certain symmetric configurations of this triple corner reflector (TCR) antenna provide sharp beams with a gain of the order of 3 dB over that of the conventional corner reflector (CR) antenna 相似文献
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Two reflector antennas are proposed. The first is constructed by adding a cylindrical reflecting surface of suitable radius to theV -shaped corner reflector antenna. The feeding element is a half-wavelength dipole. The resulting cylindrical corner reflector provided a 2 dB increase in gain, minimum sidelobe level, low input reactance, and uncritical dependence of performance on frequency. The second antenna is constructed by adding a cylindrical surface to the three-dimensional corner reflector. This extension provided an increase in gain of at least 6.5 dB, an input resistance compatible with the commercially available 50- or75-Omega coaxial cables, low input reactance, and uncritical dependence of performance on frequency. A grid-type cylindrical corner reflector antenna, and a three-dimensional corner reflector antenna with a cylindrical subsurface of finite reflecting surfaces were designed, and the measured input impedances, gains, and field patterns showed excellent agreement with the theoretical results for both antennas. 相似文献
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Giudice G.E. Kuksenkov D.V. De Peralta L.G. Temkin H. 《Photonics Technology Letters, IEEE》1999,11(12):1545-1547
Single-mode operation from an index-guided vertical-cavity surface-emitting laser (VCSEL) has been achieved by using a fiber Bragg grating (FBG) as an external selective wavelength reflector. The spectral characteristics of the external cavity controlled VCSEL under static and dynamic conditions have been studied. The FBG provided stable single mode operation under pseudorandom modulation with a sidemode suppression ratio of ~30 dB from 500 Mb/s up to 4 Gb/s at room temperature 相似文献