Optics and Laser Technology最新文献

Control of photothermal liquid jets through microbubble Regulation: Fundamental mechanisms and Developing Strategies 通过微气泡调节控制光热液体射流：基本机制与发展战略

IF 4.6 2区物理与天体物理

Optics and Laser Technology Pub Date : 2024-09-26 DOI: 10.1016/j.optlastec.2024.111845

引用次数: 0

High responsivity zero-biased Mid-IR graphene photodetector based on chalcogenide glass waveguide 基于铬化玻璃波导的高响应度零偏压中红外石墨烯光电探测器

IF 4.6 2区物理与天体物理

Optics and Laser Technology Pub Date : 2024-09-26 DOI: 10.1016/j.optlastec.2024.111852

{"title":"High responsivity zero-biased Mid-IR graphene photodetector based on chalcogenide glass waveguide","authors":"","doi":"10.1016/j.optlastec.2024.111852","DOIUrl":"10.1016/j.optlastec.2024.111852","url":null,"abstract":"<div><div>Graphene’s unique properties have made it a promising material for high-performance photodetectors due to its interesting features including broadband absorption, fast speed, and strong photothermoelectric effect. Here, an optimized waveguide photodetector incorporating double graphene layers with two cores is presented to boost the responsivity (∼twice), at Mid-IR range. The proposed structure operates in the zero-bias regime to eliminate the dark current issue associated with the zero bandgap nature of graphene and leads to lower noise equivalent power. The presented photodetector operating based on split gates to electrostatically induce the p-n junction in graphene channels, operates based on the photothermoelectric effect and provides responsivity, NEP, and 3 dB bandwidth of 6.3 V/W, 0.34 nW/Hz<sup>1/2</sup>, and 1.54 GHz, respectively for the detection at λ = 5.2 μm. The feasibility of the proposed structure is proved according to recent experimentally demonstrated photodetectors. Hence, the obtained results are reliable, in practice. The study has been accomplished by numerical simulation of mode profiles and solving the heat equation to extract the characteristics of the proposed photodetector. The zero-power consumption and tunability of the proposed structure make it a promising candidate for sensing, industrial, defense, and environmental monitoring applications with high accuracy.</div></div>","PeriodicalId":19511,"journal":{"name":"Optics and Laser Technology","volume":null,"pages":null},"PeriodicalIF":4.6,"publicationDate":"2024-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142323350","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Semantic ghost imaging based on semantic coding 基于语义编码的语义鬼影成像

IF 4.6 2区物理与天体物理

Optics and Laser Technology Pub Date : 2024-09-26 DOI: 10.1016/j.optlastec.2024.111808

{"title":"Semantic ghost imaging based on semantic coding","authors":"","doi":"10.1016/j.optlastec.2024.111808","DOIUrl":"10.1016/j.optlastec.2024.111808","url":null,"abstract":"<div><div>To address the challenge of reconstructing high-quality images under low sampling during the Ghost Imaging (GI) procedure, we propose a semantic GI method based on semantic encoding. Through training, the obtained continuous weights of the convolution kernels are served as the speckle patterns. A processing module and a Recurrent Neural Network (RNN) are then employed to decode and reconstruct the images. Both the speckle patterns and their corresponding bucket values are optimized, so that the semantic information of the target object can be better extracted. With different gated recurrent units (GRU) layers for the target objects in different datasets, the feasibility of the proposed GI method is validated by the numerical simulations and experiments on the simple target objects (the handwriting digits “0” to “9”) and more complex target objects (“NUPT”). The results show that the target objects (the handwriting digits) can be reconstructed with higher quality even at a lower sampling rate of 1.28%. Additionally, the proposed method has applicability for more complex objects (such as “NUPT”) in real applications. In comparison with those results by using traditional ghost imaging (TGI), deep convolution auto-encoder network (DCAN), and RNN-based GI (GI-RNN), the proposed GI method shows a better performance in terms of the quality of reconstructed images and the training time, that is, the proposed method can have both good reconstructed image quality and less training time. By introducing the concept of semantic communication into GI, the proposed method provides a new idea for the model-based GI.</div></div>","PeriodicalId":19511,"journal":{"name":"Optics and Laser Technology","volume":null,"pages":null},"PeriodicalIF":4.6,"publicationDate":"2024-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142322322","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Enhanced beam quality of high-energy lasers utilizing fused silica as an all-solid-state SBS-PCM 利用熔融石英作为全固态 SBS-PCM 提高高能激光器的光束质量

IF 4.6 2区物理与天体物理

Optics and Laser Technology Pub Date : 2024-09-26 DOI: 10.1016/j.optlastec.2024.111850

引用次数: 0

Efficient high-power 1.9 µm picosecond Raman laser in H2-filled hollow-core fiber without generation of rotational lines 填充 H2 的中空芯光纤中的高效大功率 1.9 µm 皮秒拉曼激光器，不会产生旋转线

IF 4.6 2区物理与天体物理

Optics and Laser Technology Pub Date : 2024-09-26 DOI: 10.1016/j.optlastec.2024.111851

引用次数: 0

Multi-parameter reconstruction of interference harmonics by effective tuning combination selection and sampling boundary fitting 通过有效的调谐组合选择和采样边界拟合实现干扰谐波的多参数重构

IF 4.6 2区物理与天体物理

Optics and Laser Technology Pub Date : 2024-09-26 DOI: 10.1016/j.optlastec.2024.111835

{"title":"Multi-parameter reconstruction of interference harmonics by effective tuning combination selection and sampling boundary fitting","authors":"","doi":"10.1016/j.optlastec.2024.111835","DOIUrl":"10.1016/j.optlastec.2024.111835","url":null,"abstract":"<div><div>To efficiently and accurately realize four-surface measurements with flexible cavity lengths and sampling frequencies, a wavelength-tuning phase-shifting matching algorithm based on harmonic selection modes is developed. The developed MPSA-AHR method utilizes pre-iterative wavefront reconstruction errors to quantitatively analyze the multi-harmonic reconstruction performance and to obtain efficient sample combinations. Combined with the densified power spectral density method, the harmonic frequencies can be obtained with high accuracy, enabling the simultaneous measurement of front/rear surfaces, thickness variation, and inhomogeneous distribution of refractive index for the tested transparent plates. The proposed method outperforms the existing methods and can realize multi-surface measurements with fewer sampling frames under the designed harmonic selecting mode, which is verified by sufficient simulations and error analysis under several measurement conditions. Repeatability measurements of a transparent plate with an average thickness of 50 mm using a Fizeau wavelength-tuning phase-shifting interferometer also verify the practical validity of our method.</div></div>","PeriodicalId":19511,"journal":{"name":"Optics and Laser Technology","volume":null,"pages":null},"PeriodicalIF":4.6,"publicationDate":"2024-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142322321","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Selective laser melting of NiTi cardiovascular stents: Processibility, surface quality and mechanical properties 选择性激光熔化镍钛心血管支架：可加工性、表面质量和机械性能

IF 4.6 2区物理与天体物理

Optics and Laser Technology Pub Date : 2024-09-25 DOI: 10.1016/j.optlastec.2024.111842

{"title":"Selective laser melting of NiTi cardiovascular stents: Processibility, surface quality and mechanical properties","authors":"","doi":"10.1016/j.optlastec.2024.111842","DOIUrl":"10.1016/j.optlastec.2024.111842","url":null,"abstract":"<div><div>Selective laser melting (SLM) is regarded as a promising alternative technology for manufacturing customized cardiovascular stents with complex geometries. In this study, a systematic study on the printability, densification and surface roughness regarding SLM of NiTi alloy were explored. It was revealed that macro cracks were mainly formed at volume energy density (VED) of 25-86 J/mm<sup>3</sup> due to insufficient energy input with un-melted powders. However, even with the same VED, the different combinations of processing parameters exhibited unique surface characteristics. After optimization, the samples with laser power of 90 W, and scanning speed of 600 mm/s exhibit a superior relative density of 99.96 % and the minimal surface roughness <em>Sq</em> of 5.992 μm. Subsequently, The SLM capability for intricate structures was demonstrated by fabricating cardiovascular stents with varying radial thicknesses. The results indicated that the surface morphologies of SLMed stents exhibit varying degrees of powder adhesion phenomenon. However, the dimensional deviation for the radial thickness of 0.2 mm exhibits a higher percentage of 72 %, whereas the deviation reaches 104 % for that of 0.6 mm. For the compression test, the thinner radial thickness stent has better recovery ability.</div></div>","PeriodicalId":19511,"journal":{"name":"Optics and Laser Technology","volume":null,"pages":null},"PeriodicalIF":4.6,"publicationDate":"2024-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142315849","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Femtosecond laser direct writing of complementary THz metasurfaces using a structured vortex beam 利用结构化涡流束以飞秒激光直接写入互补太赫兹元表面

IF 4.6 2区物理与天体物理

Optics and Laser Technology Pub Date : 2024-09-25 DOI: 10.1016/j.optlastec.2024.111831

{"title":"Femtosecond laser direct writing of complementary THz metasurfaces using a structured vortex beam","authors":"","doi":"10.1016/j.optlastec.2024.111831","DOIUrl":"10.1016/j.optlastec.2024.111831","url":null,"abstract":"<div><div>Metasurfaces, which are increasingly popular for creating ultra-thin optical components, offer a way to reduce the bulkiness of traditional optics, especially in the THz band. Typically, metasurfaces are fabricated using lithographic techniques in clean rooms, but a simpler fabrication method could expand their applicability. In this study, we present a femtosecond laser-based direct fabrication of complementary metasurfaces, highlighting the benefits of a single-step, mask-free process using structured light beams. A q-plate is used to generate an annular vortex beam with femtosecond duration, which is further tailored to imprint individual meta-atoms by perforating an Au film deposited on a Si substrate through laser ablation. This technique enables the creation of various metasurfaces designed for THz operation, as verified by full-wave simulations, featuring distinct shapes and periodicities for efficient electromagnetic radiation delivery. The fabricated devices are experimentally tested using time-domain spectroscopy, confirming the expected transmission properties and demonstrating the reliability and versatility of the proposed approach.</div></div>","PeriodicalId":19511,"journal":{"name":"Optics and Laser Technology","volume":null,"pages":null},"PeriodicalIF":4.6,"publicationDate":"2024-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142319638","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A comparative study between PCR and PLSR in a tapered optical fiber sensor for acetone detection 用于丙酮检测的锥形光纤传感器中 PCR 和 PLSR 的比较研究

IF 4.6 2区物理与天体物理

Optics and Laser Technology Pub Date : 2024-09-25 DOI: 10.1016/j.optlastec.2024.111838

引用次数: 0

Generation of harmonic mode-locked pulses and noise-like pulses in an all-PM Tm-doped fiber laser via linear-cavity interferometric NPE 通过线性腔干涉 NPE 在全调频掺铥光纤激光器中产生谐波锁模脉冲和类噪声脉冲

IF 4.6 2区物理与天体物理

Optics and Laser Technology Pub Date : 2024-09-24 DOI: 10.1016/j.optlastec.2024.111848

{"title":"Generation of harmonic mode-locked pulses and noise-like pulses in an all-PM Tm-doped fiber laser via linear-cavity interferometric NPE","authors":"","doi":"10.1016/j.optlastec.2024.111848","DOIUrl":"10.1016/j.optlastec.2024.111848","url":null,"abstract":"<div><div>This study demonstrates the generation of both harmonic mode-locking (HML) and noise-like pulses (NLPs) in an all-polarization-maintaining (PM) Tm-doped fiber laser mode-locked by a linear-cavity interferometric nonlinear polarization evolution (NPE) mechanism. Adjusting the pump power and manipulating the intra-cavity pulse distribution along the axes of the PM fiber enable transitions between fundamental mode-locking, various harmonic orders, and NLPs. In the HML regime, a 19th-order harmonic soliton pulse is achieved, marking a record-breaking repetition rate of ∼229 MHz for NPE-based all-PM linear-cavity fiber lasers. Detailed analyses of pulse characteristics across different harmonic orders are presented, with the 3rd-order HML exhibiting a high supermode suppression level. The stability of 3rd-order HML operation is further confirmed through noise evaluations and long-term assessments of power and spectrum. In the NLPs regime, the output is centered at 1962 nm with a 3-dB bandwidth of ∼30 nm, achieving an average power of 284 mW and a pulse energy of ∼24 nJ. The long-term stability and noise profile of the laser are examined to ensure sustained NLPs operation. Furthermore, the influence of pump power variations on the optical properties of NLPs is investigated, revealing an increased spectral width, red-shifted spectrum, and reduced duration of coherent peaks with higher pump intensities.</div></div>","PeriodicalId":19511,"journal":{"name":"Optics and Laser Technology","volume":null,"pages":null},"PeriodicalIF":4.6,"publicationDate":"2024-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142315848","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0