Optics and Laser Technology最新文献_第5页

Alamouti coding enabled polarization insensitive simplified self-homodyne coherent system for short-reach optical interconnects 用于短距离光互连的阿拉木图编码启用偏振不敏感简化自同调相干系统

IF 4.6 2区物理与天体物理 Q1 OPTICS

Optics and Laser Technology

Pub Date : 2024-11-25 DOI: 10.1016/j.optlastec.2024.112164

Wei Wang , Dongdong Zou , Zhenpeng Wu , Qi Sui , Dongmei Huang , Chao Lu , Fan Li

Coherent technology inherent with more available degrees of freedom is deemed as a competitive solution for next-generation ultra-high-speed short-reach optical interconnects. However, the high system cost, elevated power consumption, and large footprint size pose formidable barriers to the application of conventional coherent systems in short-reach scenarios. Self-homodyne coherent detection exhibits its potential for short-reach applications due to the sharing of the signal carrier and the local oscillator (LO), which not only reduces the system cost but also eliminates the frequency offset. Nevertheless, the self-homodyne coherent technique suffers from the polarization fading issue due to the random polarization states of the remote LO. In this paper, an Alamouti coding enabled simplified self-homodyne coherent detection technique is proposed to solve the polarization fading issue, resulting in a polarization-insensitive receiver. Besides, to further reduce the computational complexity of the system, the digital subcarrier multiplexing (DSCM) technique is discussed to alleviate the complexity of chromatic dispersion compensation (CDC), which is another dominant power consumption module of the receiver-side digital signal processing. The performance of the proposed scheme is demonstrated with a 50Gbaud 4-subcarrier 16/32QAM DSCM signal. The results show that polarization-insensitive self-homodyne detection is achieved by the transmitter-side Alamouti coding technique, circumventing the sophisticated automatic polarization controller for the polarization state tracking of the remote LO. In addition, by applying the joint dispersion compensation and equalization (JDCE) method for the DSCM signal, the CD-induced penalty can be fully addressed by increasing 4 taps in the equalizer for an 80 km single-mode fiber transmission without an individual CDC module, reducing the computational complexity of the system significantly.

具有更多可用自由度的固有相干技术被认为是下一代超高速短距离光互连的竞争性解决方案。然而，系统成本高、功耗大、占地面积大，这些都对传统相干系统在短距离应用中构成了巨大障碍。由于共用信号载波和本地振荡器（LO），不仅降低了系统成本，还消除了频率偏移，因此自同源相干检测在短距离应用中展现出巨大潜力。然而，由于远程 LO 的随机极化状态，自同调相干技术存在极化衰减问题。本文提出了一种支持阿拉木图编码的简化自同调相干检测技术，以解决极化衰减问题，从而实现对极化不敏感的接收器。此外，为了进一步降低系统的计算复杂度，本文还讨论了数字子载波复用（DSCM）技术，以减轻色度色散补偿（CDC）的复杂性，而色度色散补偿是接收端数字信号处理的另一个主要功耗模块。使用 50Gbaud 4 子载波 16/32QAM DSCM 信号演示了拟议方案的性能。结果表明，通过发射端 Alamouti 编码技术实现了对偏振不敏感的自同调检测，避开了用于远程 LO 偏振状态跟踪的复杂自动偏振控制器。此外，通过对 DSCM 信号采用联合色散补偿和均衡（JDCE）方法，在 80 千米单模光纤传输中，无需单独的 CDC 模块，只需在均衡器中增加 4 个抽头，就能完全解决 CD 引起的惩罚问题，从而大大降低了系统的计算复杂性。

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引用次数: 0

Numerical analysis of All-Optical universal NAND and NOR photonic crystal logic gates by creating holes in silicon material 通过在硅材料上开孔实现全光通用 NAND 和 NOR 光子晶体逻辑门的数值分析

IF 4.6 2区物理与天体物理 Q1 OPTICS

Optics and Laser Technology

Pub Date : 2024-11-25 DOI: 10.1016/j.optlastec.2024.112197

Fariborz Parandin, Pouya Karami

All-optical NAND and NOR logical gates based on two-dimensional photonic crystals have been designed and analyzed in this research. A hole in the silicon substrate was created to design the desired gates, and the light emission analysis was performed using the FDTD numerical method. Most of the circuits that have been designed so far based on photonic crystals have included dielectric rods in the airfield. This research uses a hole in the silicon substrate, which is more suitable for fabrication. The proposed structure is created symmetrically using a small photonic crystal. The simulation results show that this small structure can be used as two NAND and NOR gates, which have a suitable power difference in the upper and lower logic states. Therefore, the proposed structure is suitable for precise logic circuits and high transmission speed. Due to the simplicity of structure and small size, the output stable time for NAND and NOR gates are 0.9 ps and 0.67 ps, respectively, indicating the gates’ low delay time. Also, the value of the contrast ratio for NAND and NOR gates is 7.26 dB and 6.35 dB, respectively, which indicates the appropriate power difference in the upper and lower logic states.

本研究设计并分析了基于二维光子晶体的全光 NAND 和 NOR 逻辑门。为了设计所需的栅极，在硅衬底上开了一个孔，并使用 FDTD 数值方法进行了光发射分析。迄今为止，基于光子晶体设计的大多数电路都在气场中加入了介质棒。这项研究在硅衬底上开孔，更适合制造。所提出的结构是利用小型光子晶体对称制作的。仿真结果表明，这种小型结构可用作两个 NAND 和 NOR 门，在上下逻辑状态下具有适当的功率差。因此，所提出的结构适用于精密逻辑电路和高速传输。由于结构简单、体积小，NAND 门和 NOR 门的输出稳定时间分别为 0.9 ps 和 0.67 ps，表明门的延迟时间很短。此外，NAND 门和 NOR 门的对比度值分别为 7.26 dB 和 6.35 dB，这表明在上下逻辑状态下有适当的功率差。

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引用次数: 0

High-power pulsed Raman fiber laser with wavelength over 2.4 μm 波长超过 2.4 μm 的高功率脉冲拉曼光纤激光器

IF 4.6 2区物理与天体物理 Q1 OPTICS

Optics and Laser Technology

Pub Date : 2024-11-25 DOI: 10.1016/j.optlastec.2024.112170

Meng Wang , Deqin Ouyang , Yewang Chen , Minqiu Liu , Junqing Zhao , Zhijian Zheng , Chunbo Li , Shuangchen Ruan

In this paper, the compact high-power pulsed Raman fiber lasers based on single-pass stimulated Raman scattering have been experimentally presented. Home-built noise-like pulse laser centered at ∼1994.7 nm with an envelope width of ∼20.8 ns was utilized as the pump laser, which can provide a maximal output power of ∼19.1 W without a notable spectral broadening. The 1st-order Raman laser operated at ∼2190.8 nm with a maximal output power of ∼4.11 W and a spectral purity of ∼93 % was achieved. Furthermore, by finely optimizing the length of Raman-gain fiber, the 2nd-order Raman laser centered at ∼2408.5 nm with a maximal power of ∼2.36 W was achieved, which represents the maximal value of Raman laser at 2.4 μm in silica-core fiber, to the best of our knowledge. The high-power pulsed Raman fiber lasers may have the potential applications in polymer material processing and spectroscopy.

本文通过实验展示了基于单通受激拉曼散射的紧凑型高功率脉冲拉曼光纤激光器。利用自制的以 1994.7 nm 为中心、包络宽度为 20.8 ns 的类噪声脉冲激光器作为泵浦激光器，可提供 19.1 W 的最大输出功率，且无明显的光谱展宽。一阶拉曼激光器的工作波长为 2190.8 纳米，最大输出功率为 4.11 瓦，光谱纯度为 93%。此外，通过精细优化拉曼增益光纤的长度，实现了以 ∼2408.5 nm 为中心、最大功率为 ∼2.36 W 的二阶拉曼激光器，这代表了目前我们所知的硅芯光纤中 2.4 μm 拉曼激光器的最大值。高功率脉冲拉曼光纤激光器在高分子材料加工和光谱学方面具有潜在的应用前景。

引用次数: 0

Influence and mechanism of ultrafast laser-textured Cu substrate on wetting behavior of SAC305 solder 超快激光纹理铜基板对 SAC305 焊料润湿行为的影响和机理

IF 4.6 2区物理与天体物理 Q1 OPTICS

Optics and Laser Technology

Pub Date : 2024-11-25 DOI: 10.1016/j.optlastec.2024.112190

Tao Ma , Zhihang Zhang , Shiqiang Zhang , Yue Zhao , Wei Shao , Jihua Huang , Shuhai Chen , Zheng Ye , Wanli Wang , Jian Yang

Periodic arrays of grids, micro-cones, and grooves were successfully fabricated on Cu substrate using ultrafast laser technology. The wetting behavior of SAC305 solder on micro-nano structured Cu substrates was investigated, and the influence mechanism of superficial micro-nano structure was discussed using classical wetting model and molecular dynamics (MD) simulation. The results indicate that compared to polished surface, all the superficial micro-nano structures on Cu substrate improve the wettability and wetting kinetics of SAC305 solder. Especially, grid structure shows the most significant improvement, and the effect is further enhanced with the increase of processing depth. When the processing depth of grid structure is 25 μm, the smallest wetting angle of 15.1° and wetting equilibrium time of 29 s were achieved. The wetting process of SAC305 solder on Cu substrate is composed of rapid reaction stage, stable diffusion state, and equilibrium stage. Rⁿ ∼ t relationship curve reveals that the influence of micro-nano structure on wetting kinetics mainly occurs in the rapid reaction stage. The enhancement of wettability and wetting kinetics from superficial micro-nano structure can be attributed to the introduced extra capillary force and the improved atomic diffusion rate on the wetting interface.

利用超快激光技术在铜基底上成功制造出了周期性的网格、微锥和凹槽阵列。利用经典润湿模型和分子动力学（MD）模拟研究了 SAC305 焊料在微纳结构铜基底上的润湿行为，并探讨了表层微纳结构的影响机理。结果表明，与抛光表面相比，铜基底上的所有表层微纳结构都能改善 SAC305 焊料的润湿性和润湿动力学。尤其是栅格结构的改善效果最为显著，而且随着加工深度的增加，效果会进一步增强。当网格结构的加工深度为 25 μm 时，达到的最小润湿角为 15.1°，润湿平衡时间为 29 s。SAC305 焊料在铜基板上的润湿过程由快速反应阶段、稳定扩散状态和平衡阶段组成。Rn ∼ t 关系曲线表明，微纳结构对润湿动力学的影响主要发生在快速反应阶段。表层微纳结构对润湿性和润湿动力学的增强可归因于润湿界面上引入的额外毛细管力和原子扩散速率的提高。

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引用次数: 0

Vibration monitoring of rotating shafts using DIC and compressed sensing 利用 DIC 和压缩传感对旋转轴进行振动监测

IF 4.6 2区物理与天体物理 Q1 OPTICS

Optics and Laser Technology

Pub Date : 2024-11-25 DOI: 10.1016/j.optlastec.2024.112189

Yuchen Wei , Yongsheng Huang , Haipan Wu , Penglong Wang , Bing Chen , Zeren Gao , Yu Fu

Monitoring vibrations in rotating shafts is essential for diagnosing and detecting mechanical faults. Digital image correlation (DIC), an optical full-field measurement technique, is increasingly employed in experimental mechanics. This study introduces a novel measurement approach that combines DIC with compressed sensing to monitor high-speed rotating shafts accurately. Traditionally, analyzing rotating shafts requires high-speed sampling devices, which increases experimental costs and reduces spatial resolution. To overcome these limitations, a random exposure sampling method was developed to capture speckle images on the shaft surface with a low frame-rate camera. By leveraging compressed sensing and DIC, the method reconstructs high-speed vibration signals from captured images. Step motion experiments demonstrated that the DIC system achieves a measurement accuracy of 10 µm. Experimental validation was conducted using various setups, including low-speed motors, high-speed rotating shafts, and milling machines, demonstrating the effectiveness of the approach. The measurement results of rotating shafts at 1200 rpm and 6000 rpm, compared with those obtained from laser Doppler vibrometry, demonstrated the effectiveness of the method in vibration measurement. Additionally, experiments on a milling machine showed that vibrations reconstructed using compressed sensing closely matched those measured with a high-speed camera. This measurement system shows significant potential for accurately assessing vibrations in high-speed rotating shafts, offering valuable insights for machinery monitoring and fault diagnosis.

监测旋转轴的振动对于诊断和检测机械故障至关重要。数字图像相关（DIC）是一种光学全场测量技术，在实验力学中的应用越来越广泛。本研究介绍了一种新颖的测量方法，它将 DIC 与压缩传感技术相结合，可对高速旋转轴进行精确监测。传统上，分析旋转轴需要高速采样设备，这会增加实验成本并降低空间分辨率。为了克服这些限制，我们开发了一种随机曝光采样方法，用低帧率相机捕捉轴表面的斑点图像。通过利用压缩传感和 DIC，该方法可从捕获的图像中重建高速振动信号。阶跃运动实验表明，DIC 系统的测量精度达到了 10 µm。实验验证使用了各种设置，包括低速电机、高速旋转轴和铣床，证明了该方法的有效性。对转速分别为 1200 转/分和 6000 转/分的旋转轴的测量结果与激光多普勒测振仪的测量结果进行了比较，证明了该方法在振动测量中的有效性。此外，在一台铣床上进行的实验表明，利用压缩传感技术重建的振动与高速照相机测量的振动非常接近。该测量系统在准确评估高速旋转轴的振动方面显示出巨大的潜力，为机械监测和故障诊断提供了宝贵的见解。

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引用次数: 0

Fabrication and quality improvement of film cooling holes via picosecond laser drilling assisted by waterjet and post-electrochemical machining 通过皮秒激光钻孔并辅以水刀和电化学后加工，制作薄膜冷却孔并提高其质量

IF 4.6 2区物理与天体物理 Q1 OPTICS

Optics and Laser Technology

Pub Date : 2024-11-25 DOI: 10.1016/j.optlastec.2024.112162

Hao Zhu , Wenbo Xie , Wenwu Du , Qinglin Zhang , Hao Yuan , Kun Xu , Yang Liu , Jingtao Wang , Viboon Saetang , Zhaoyang Zhang

Film cooling holes (FCHs) are of superior importance for blade protection and performance improvement in aircraft engine, while their fabrication requires high efficiency, high precision and extremely good surface quality, making it a challenging task. In this study, the ultrashort picosecond (ps) laser is employed to drill the FCHs on the DD6 single crystal superalloy, based on which the assisted waterjet is further introduced to reduce thermal damage, and the electrochemical machining (ECM) is also added as a post-processing manner for further quality improvement. It has been found through orthogonal tests that the pulse repetition frequency possessing most significant influence on hole taper during direct ps-laser drilling. The introduced low-pressure waterjet effectively eliminates the thermal damage such as slag attachment and recast layer, and the waterjet angle affects the hole profile obviously. After conducting post-ECM, the hole taper decreases continuously with an increase in processing time and applied voltage. In addition, the laser-induced periodic surface structure (LIPSS) has been observed on the sidewall, while an obvious decrease in LIPSS wavelength has been confirmed after post processing. Moreover, simulation study of temperature evolution is carried out by developing a two-temperature model, demonstrating that the lattice temperature surpasses the boiling point within 0.182 ps, and the ablation can be precisely localized within laser irradiation zone. The simulation of flow field on DD6 surface has also been conducted, and the distributions of flow velocity, pressure and thickness are obtained, which helps understand the effect of waterjet on the drilling process.

薄膜冷却孔（FCHs）对飞机发动机叶片的保护和性能的提高具有极其重要的意义，而其制造要求高效率、高精度和极好的表面质量，因此是一项具有挑战性的任务。本研究采用超短皮秒 (ps) 激光在 DD6 单晶超合金上钻削 FCH，在此基础上进一步引入辅助水刀以减少热损伤，并增加电化学加工 (ECM) 作为后处理方式以进一步提高质量。通过正交试验发现，在直接ps 激光钻孔过程中，脉冲重复频率对孔锥度的影响最大。引入的低压水刀能有效消除熔渣附着和再铸层等热损伤，水刀角度对孔轮廓的影响也很明显。进行后电化学处理后，随着处理时间和施加电压的增加，孔锥度不断减小。此外，在侧壁上还观察到了激光诱导的周期性表面结构（LIPSS），并证实后处理后 LIPSS 波长明显减小。此外，还通过建立双温模型对温度演变进行了模拟研究，结果表明晶格温度在 0.182 ps 内就超过了沸点，而且烧蚀可以在激光照射区内精确定位。此外，还对 DD6 表面的流场进行了模拟，得到了流速、压力和厚度的分布，有助于理解水刀对钻孔过程的影响。

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引用次数: 0

Effect of combined treatment of laser shock peening and shot peening on fatigue performance of laser-powder-bed-fusioned GH4169 nickel-based alloy 激光冲击强化和喷丸强化联合处理对激光粉末床熔融 GH4169 镍基合金疲劳性能的影响

IF 4.6 2区物理与天体物理 Q1 OPTICS

Optics and Laser Technology

Pub Date : 2024-11-24 DOI: 10.1016/j.optlastec.2024.112141

Peixuan Ouyang , Zhichao Dong , Xuekun Luo , Shuting Zhang , Lu Liu , Bin Sun , Lijie Zhou

The laser-powder-bed-fusioned (LPBFed) GH4169 nickel-based alloys were respectively surface-strengthened by laser shock peening (LSP), shot peening (SP), and a combination of LSP and SP (LSP + SP). The surface roughness, microhardness, residual stress, and microstructures of the un-peened, (LSP + SP)ed, LSPed, and SPed sample were comparatively studied. The fatigue gain mechanism of the LSP + SP combined treatment on the LPBFed alloy was finally revealed. The vibration fatigue life of the (LSP + SP)ed sample under 680 MPa is at least 37.76 times, 1.58 times, and 0.79 times longer compared with the un-peened LSPed and SPed samples. The LSP + SP treatment decreased the stress concentration coefficient K_t compared with LSP treatment. The maximum compressive residual stress (CRS) of the (LSP + SP)ed sample is 68 % larger than that of the LSPed sample, and the CRS layer thickness is 1.12 times thicker compared with the SPed sample. The average grain size for the (LSP + SP)ed sample is the smallest, and the LAGBs fraction increases by 96 % and 50.9 % compared with the LSPed and SPed samples. The fatigue gain mechanism of the LSP + SP combined treatment on the LPBFed alloy is concluded that the largest maximum CRS, a thick CRS layer, the refined grains, and the decreased K_t extend the crack initiation life, and the smallest grain size, the highest density of dislocation substructures, as well as the highest fraction of LAGBs extend the crack propagation life. The results demonstrated that the LSP + SP combined treatment is an efficient surface strengthening method that can improve fatigue life of LPBFed nickel-based alloys.

分别通过激光冲击强化（LSP）、喷丸强化（SP）以及 LSP 和 SP 组合（LSP + SP）对激光粉末床熔化（LPBFed）GH4169 镍基合金进行了表面强化。比较研究了未强化、（LSP + SP）强化、LSP强化和SP强化样品的表面粗糙度、显微硬度、残余应力和显微组织。最终揭示了 LSP + SP 组合处理对 LPBFed 合金的疲劳增益机理。在 680 兆帕下，经过（LSP + SP）处理的样品的振动疲劳寿命比未经强化处理的 LSPed 和 SPed 样品至少延长了 37.76 倍、1.58 倍和 0.79 倍。与 LSP 处理相比，LSP + SP 处理降低了应力集中系数 Kt。经（LSP + SP）处理的样品的最大压缩残余应力（CRS）比经 LSP 处理的样品大 68%，CRS 层厚度是经 SP 处理样品的 1.12 倍。(LSP + SP)ed 样品的平均晶粒尺寸最小，与 LSPed 和 SPed 样品相比，LAGBs 分数分别增加了 96% 和 50.9%。LSP+SP组合处理对LPBFed合金的疲劳增益机理的结论是：最大的CRS、厚的CRS层、细化的晶粒和降低的Kt延长了裂纹起始寿命，而最小的晶粒尺寸、最高密度的位错子结构以及最高比例的LAGBs延长了裂纹扩展寿命。结果表明，LSP + SP 组合处理是一种高效的表面强化方法，可提高 LPBFed 镍基合金的疲劳寿命。

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引用次数: 0

Influence of crystal orientation and incident plane on n-type 4H-SiC wafer slicing by using picosecond laser 晶体取向和入射面对使用皮秒激光切割 n 型 4H-SiC 硅片的影响

IF 4.6 2区物理与天体物理 Q1 OPTICS

Optics and Laser Technology

Pub Date : 2024-11-24 DOI: 10.1016/j.optlastec.2024.112174

Yongping Yao , Qiu Chen , Bixue Li , Jianfei Zhang , Rongkun Wang , Meng Bai , Runze Liang , Longnan Ma , Tiejun Ma , Jiayu Zhang , Jinbao Xia , Hongkun Nie , Baitao Zhang

Laser slicing has been considered as the most efficient technique for slicing SiC wafers with the advantages of small kerf width (loss) and crack, low roughness on cleaved surface, high quality and efficiency, etc. Here, laser slicing of n-type 4H-SiC was demonstrated by using a homemade 1064 nm picosecond laser combined with mechanical stretch stripping. The influence of laser processing along [11

\bar{2}

0] and [1

\bar{1}

00] crystal orientations on Si-face and C-face of n-type 4H-SiC, specifically on the internal laser ablation lines and cracks, the peeling tensile strength, and the surface roughness of the peeled surfaces was investigated. The semi-insulating 4H-SiC wafer laser slicing was conducted for comparison. Under the same laser conditions, laser slicing of semi-insulating 4H-SiC was easier than that of n-type. The laser modification quality along [1

\bar{1}

00] orientation was better than that along [11

\bar{2}

0] orientation for both the semi-insulating and n-type 4H-SiC and the reasons were explained. The results indicated that the optimal laser slicing scheme detailed laser scanning along [1

\bar{1}

00] orientation and incidence from the C-face. Finally, a 6-inch, 420.36 µm-thick n-type 4H-SiC wafer was successfully sliced.

激光切片具有切口宽度（损耗）和裂缝小、切割表面粗糙度低、质量和效率高等优点，被认为是切割碳化硅晶片最有效的技术。在此，使用自制的 1064 nm 皮秒激光器结合机械拉伸剥离，演示了 n 型 4H-SiC 的激光切片。研究了沿 n 型 4H-SiC Si 面和 C 面[11 2¯ 0]和[1 1¯ 00]晶向激光加工的影响，特别是对内部激光烧蚀线和裂纹、剥离拉伸强度和剥离表面粗糙度的影响。作为对比，还对半绝缘 4H-SiC 硅片进行了激光切片。在相同的激光条件下，半绝缘 4H-SiC 的激光切片比 n 型更容易。半绝缘和 n 型 4H-SiC 沿[1 1¯ 00]方向的激光修饰质量均优于沿[11 2¯ 0]方向的激光修饰质量，并解释了原因。结果表明，最佳激光切片方案是沿[1 1¯ 00]方向和从 C 面入射进行详细的激光扫描。最后，一个 6 英寸、420.36 µm 厚的 n 型 4H-SiC 硅片被成功切割。

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引用次数: 0

Demonstration of a three-active-section DFB laser with photon-photon resonance and detuned loading effects to obtain enhanced bandwidth and maintained high output power 演示具有光子-光子共振和失谐加载效应的三有源截面 DFB 激光器，以获得更高带宽并保持高输出功率

IF 4.6 2区物理与天体物理 Q1 OPTICS

Optics and Laser Technology

Pub Date : 2024-11-24 DOI: 10.1016/j.optlastec.2024.112127

Xiang Ma , Hefei Qi , Yuedi Ding , Boyuan Liu , Wenqi Yu , Shaobo Li , Weihua Guo

Enhancement of the modulation bandwidth of the directly modulated semiconductor laser has attracted tremendous attention for applications in optical fiber communication and optical interconnects. However, modulation bandwidth is enhanced by some special technology such as integrating the active region or passive region regularly, which lead to low power and complex fabrication. Here we design and demonstrate a monolithic integrated three-active-section distributed feedback (TAS-DFB) laser with enhanced bandwidth theoretically and experimentally. The laser includes three sections: the DFB section, feedback section and active phase section. The three sections share the same multiple quantum-well structure. To enhance the modulation bandwidth beyond the intrinsic modulation bandwidth, both photon-photon resonance (PPR) and detuned loading (DL) effects are utilized to achieve over 55 GHz. The active phase section shows promise in achieving high bandwidth with PPR and relatively high output power of ∼ 10 mW at 25 °C under continuous-wave (CW) operation simultaneously. The fabrication process of the TAS-DFB laser is simplified due to the conventional and identical active layer structure.

提高直接调制半导体激光器的调制带宽在光纤通信和光互连领域的应用引起了极大关注。然而，调制带宽的增强需要采用一些特殊技术，如将有源区或无源区有规律地集成在一起，从而导致低功耗和复杂的制造工艺。在此，我们设计并演示了一种具有更高带宽的单片集成三有源段分布式反馈（TAS-DFB）激光器，并对其进行了理论和实验验证。该激光器包括三个部分：DFB 部分、反馈部分和有源相位部分。这三个部分共享相同的多量子阱结构。为了提高调制带宽，使其超过固有调制带宽，利用了光子光子共振（PPR）和失谐加载（DL）效应，从而实现了超过 55 GHz 的调制带宽。有源相位部分显示出利用 PPR 实现高带宽的前景，同时在连续波（CW）工作条件下，在 25 °C 温度下可实现 ∼ 10 mW 的相对较高输出功率。由于采用了传统的相同有源层结构，TAS-DFB 激光器的制造工艺得以简化。

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引用次数: 0

Optical algorithm for derivative of real-valued functions 实值函数导数的光学算法

IF 4.6 2区物理与天体物理 Q1 OPTICS

Optics and Laser Technology

Pub Date : 2024-11-24 DOI: 10.1016/j.optlastec.2024.112137

Murilo H. Magiotto, Guilherme L. Zanin, Wesley B. Cardoso, Ardiley T. Avelar, Rafael M. Gomes

The derivation of a function is a fundamental tool for solving problems in calculus. Consequently, the motivations for investigating physical systems capable of performing this task are numerous. Furthermore, the potential to develop an optical computer to replace conventional computers has led us to create an optical algorithm and propose an experimental setup for implementing the derivative of one-dimensional real-valued functions using a paraxial and monochromatic laser beam. To complement the differentiation algorithm, we have experimentally implemented a novel optical algorithm that can transfer a two-dimensional phase-encoded function to the intensity profile of a light beam. Additionally, we demonstrate how to extend the optical algorithm to implement high-order derivatives of two-dimensional real-valued functions encoded in the phase of the transverse profile of photons.

函数求导是解决微积分问题的基本工具。因此，研究能够完成这一任务的物理系统的动机是多方面的。此外，开发光学计算机以取代传统计算机的潜力促使我们创建了一种光学算法，并提出了一种利用准轴向单色激光束实现一维实值函数导数的实验装置。作为对微分算法的补充，我们通过实验实现了一种新型光学算法，可将二维相位编码函数转移到光束的强度曲线上。此外，我们还演示了如何扩展光学算法，以实现光子横向剖面相位编码的二维实值函数的高阶导数。

引用次数: 0