Optics letters最新文献_第3页

Microsphere-assisted Raman scattering enhancement by photonic nanojet: the role of the collection system. 光子纳米射流增强微球辅助拉曼散射：收集系统的作用。

IF 3.3 2区物理与天体物理

Optics letters Pub Date : 2025-10-01 DOI: 10.1364/OL.574338

Vlatko Gašparić, David Zopf, Thomas G Mayerhöfer, Jürgen Popp, Mile Ivanda

{"title":"Microsphere-assisted Raman scattering enhancement by photonic nanojet: the role of the collection system.","authors":"Vlatko Gašparić, David Zopf, Thomas G Mayerhöfer, Jürgen Popp, Mile Ivanda","doi":"10.1364/OL.574338","DOIUrl":"https://doi.org/10.1364/OL.574338","url":null,"abstract":"The use of a microlens to create a strong and narrow beam of light called a photonic nanojet (PNJ) has attracted a lot of attention in the scientific community lately. Especially important is its use for Raman scattering enhancement. However, its mechanism is still not clear. While research in the literature has so far concentrated on the excitation part of the problem (PNJ), we investigate the role of the collection system for the enhancement. Detailed and systematic vertical Raman imaging measurements were performed. By experimental optimization of the collection system parameters, up to 19.29× enhancement was achieved. A simple theoretical model is created that calculates the effective numerical aperture (NAeff) of the microsphere-objective system, from which it computes the enhancement. The comparison between the experimentally measured enhancement and the calculated enhancement from the model shows that the collection system plays a major role. The model surprisingly well matches the experimental data, and with possible improvements in the future, it could open a new door in explaining and predicting microsphere-assisted Raman enhancement.","PeriodicalId":19540,"journal":{"name":"Optics letters","volume":"50 19","pages":"6012-6015"},"PeriodicalIF":3.3,"publicationDate":"2025-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145207296","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

Non-phase-shift Fourier single-pixel imaging with conjugate symmetry of the Fourier spectrum and ADMM-based image inpainting. 傅立叶谱共轭对称的非相移傅立叶单像素成像及基于admm的图像补绘。

IF 3.3 2区物理与天体物理

Optics letters Pub Date : 2025-10-01 DOI: 10.1364/OL.575751

Rui Sun, Yi Ding, Jiaye Kuang, Jingjing Cheng, Ryszard Buczynski, Wenzhong Liu

引用次数: 0

Time geometric spin Hall effect of a spatiotemporal optical vortex. 时空光学涡旋的时间几何自旋霍尔效应。

IF 3.3 2区物理与天体物理

Optics letters Pub Date : 2025-10-01 DOI: 10.1364/OL.569255

Weifeng Ding, Chaokai Yang, Zhaoying Wang

引用次数: 0

Pulse energy scaling of femtosecond laser-generated stress waves inside fused silica. 熔融石英内飞秒激光产生应力波的脉冲能量标度。

IF 3.3 2区物理与天体物理

Optics letters Pub Date : 2025-10-01 DOI: 10.1364/OL.568702

Olga Koritsoglou, Guillaume Duchateau, Olivier Utéza, Alexandros Mouskeftaras

引用次数: 0

Cost-effective ultra-depth-of-field Fourier ptychographic microscopy. 具有成本效益的超景深傅立叶平面显微镜。

IF 3.3 2区物理与天体物理

Optics letters Pub Date : 2025-10-01 DOI: 10.1364/OL.572022

Nian Pan, Jingchuan Zuo, Xiuwen Wang, Qun Hao, Shaohui Zhang

{"title":"Cost-effective ultra-depth-of-field Fourier ptychographic microscopy.","authors":"Nian Pan, Jingchuan Zuo, Xiuwen Wang, Qun Hao, Shaohui Zhang","doi":"10.1364/OL.572022","DOIUrl":"https://doi.org/10.1364/OL.572022","url":null,"abstract":"Fourier ptychographic microscopy (FPM) is a promising computational imaging technique that achieves high space-bandwidth product (SBP) quantitative complex amplitude imaging through synergistic integration of phase retrieval and synthetic aperture methodologies. However, conventional FPM struggles with defocusing issues when the sample exhibits non-planar distribution characteristics or is positioned at a non-ideal pose, which can cause the sample to be beyond the system's focal range, degrading the quality of the reconstructed image. In this paper, we propose a cost-effective solution to achieve ultra-depth of field (DOF) FPM. With the defocus distance calculated from the lateral shift under oblique illumination, we can drive a photographic lens, which serves as a tunable tube lens, to refocus along the axial direction. By computationally fusing reconstructed images acquired at distinct focal planes using FPM, the system achieves ultra-DOF while preserving native imaging performance. Experimental results show that the DOF of a 10× objective with a numerical aperture (NA) of 0.25 can be significantly extended from 9.24 μm to 300 μm, achieving an improvement of up to 30 times.","PeriodicalId":19540,"journal":{"name":"Optics letters","volume":"50 19","pages":"6032-6035"},"PeriodicalIF":3.3,"publicationDate":"2025-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145207228","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

Highly dispersive energy-managed soliton fiber laser. 高色散能量管理孤子光纤激光器。

IF 3.3 2区物理与天体物理

Optics letters Pub Date : 2025-10-01 DOI: 10.1364/OL.574002

Mostafa I Mohamed, Amala Jose, Aurélien Coillet, Patrice Tchofo Dinda, Nithyanandan Kanagaraj, Philippe Grelu

引用次数: 0

Watt-level single-frequency lasing enabled by an Er³⁺-doped fluoride fiber ring oscillator at 2.79 μm. 2.79 μm掺杂Er3+的氟化物光纤环形振荡器实现了瓦级单频激光。

IF 3.3 2区物理与天体物理

Optics letters Pub Date : 2025-10-01 DOI: 10.1364/OL.576990

Yuanbao Zhang, Hongyu Luo, Chenhao Sun, Xinying Tan, Xiangyu Zhao, Jianfeng Li, Yong Liu

引用次数: 0

Low-loss, gap-filling, nested, anti-resonant nodeless fiber in the ultraviolet band. 低损耗、空隙填充、嵌套、抗谐振紫外波段无节点光纤。

IF 3.3 2区物理与天体物理

Optics letters Pub Date : 2025-10-01 DOI: 10.1364/OL.572825

Tong Li, Yaping Liu, Zhiqun Yang, Zhanhua Huang, Lin Zhang

{"title":"Low-loss, gap-filling, nested, anti-resonant nodeless fiber in the ultraviolet band.","authors":"Tong Li, Yaping Liu, Zhiqun Yang, Zhanhua Huang, Lin Zhang","doi":"10.1364/OL.572825","DOIUrl":"https://doi.org/10.1364/OL.572825","url":null,"abstract":"We propose what we believe to be a novel low-loss, gap-filling, nested, anti-resonant nodeless fiber (GF-NANF) designed for ultraviolet (UV) applications. The GF-NANF achieves loss reduction by integrating nested tubes and gap-filling structures. Our results show that the GF-NANF reduces confinement loss by four orders of magnitude to 2.29 × 10-5 dB/m, and propagation loss by two orders of magnitude to 1.64 × 10-2 dB/m, at 355 nm, when compared to an ARF of the same design that lacks both gap-filling cladding tubes and nested cladding tubes. Additionally, the fiber shows simulated low bending losses of 1.01 × 10-4 dB/m at a 10-cm bending radius and 1.40 × 10-3 dB/m at 5 cm, representing a reduction by approximately three orders of magnitude compared to the NANF without gap-filling tubes. Notably, at a bending radius of 10 cm, the GF-NANF maintains quite low bending losses below 1.2 × 10-4 dB/m across all bending orientations from 0° to 360°, significantly lower than that of structures without gap-filling tubes, exhibiting its suitability for UV optical systems requiring high efficiency and operation flexibility.","PeriodicalId":19540,"journal":{"name":"Optics letters","volume":"50 19","pages":"6157-6160"},"PeriodicalIF":3.3,"publicationDate":"2025-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145207268","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

Investigating the impact of substrate defects on Ga₂O₃/GaN-based ultraviolet photodetector by designing a common-connected electrode. 通过设计共连接电极，研究了衬底缺陷对Ga2O3/ gan基紫外光电探测器的影响。

IF 3.3 2区物理与天体物理

Optics letters Pub Date : 2025-10-01 DOI: 10.1364/OL.574719

Chunshuang Chu, Longyu Wang, Yan Li, Yonghui Zhang, Ke Jiang, Xiaojuan Sun, Dabing Li, Zi-Hui Zhang

{"title":"Investigating the impact of substrate defects on Ga2O3/GaN-based ultraviolet photodetector by designing a common-connected electrode.","authors":"Chunshuang Chu, Longyu Wang, Yan Li, Yonghui Zhang, Ke Jiang, Xiaojuan Sun, Dabing Li, Zi-Hui Zhang","doi":"10.1364/OL.574719","DOIUrl":"https://doi.org/10.1364/OL.574719","url":null,"abstract":"Ga2O3/GaN hybrid ultraviolet (UV) photodetector (PD) has photon-carriers generated in the Ga2O3 region and transported in the GaN layer. In this work, by designing Ga2O3/GaN UV PD with a gate metal on the Ga2O3 surface, common-connected with the cathode on the GaN layer, we have revealed that the impact of substrate defects in the GaN region on the photo-generated carrier transport is significant for Ga2O3/GaN UV PD. As a result, we have observed asymmetric current in terms of the anode bias of different polarities. According to our measurement, the photocurrent of 8.81 × 10-5 A/cm2/2.34 × 10-5 A/cm2, the responsivity of 6.65 A/W/1.16 A/W, the rise time of 1.07 s/1.14 s, and the fall time of 1.16 s/1.35 s are achieved at the anode bias of -6 V/+6 V, respectively. When the anode is biased positively, the poorer performances are well attributed to the substrate defects, such that Ga2O3/GaN UV PD pushes the photo-generated carriers deep into the more defected GaN substrate region. This observation is further proven by the developed physical models.","PeriodicalId":19540,"journal":{"name":"Optics letters","volume":"50 19","pages":"5957-5960"},"PeriodicalIF":3.3,"publicationDate":"2025-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145207312","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

Imaging properties of microsphere-assisted microscopy under transmitted illumination. 透射照明下微球辅助显微镜的成像特性。

IF 3.3 2区物理与天体物理

Optics letters Pub Date : 2025-10-01 DOI: 10.1364/OL.575004

Hongmei Guo, Rong Huang, Yulu Sun, Yurong Cao, Yong-Hong Ye

{"title":"Imaging properties of microsphere-assisted microscopy under transmitted illumination.","authors":"Hongmei Guo, Rong Huang, Yulu Sun, Yurong Cao, Yong-Hong Ye","doi":"10.1364/OL.575004","DOIUrl":"https://doi.org/10.1364/OL.575004","url":null,"abstract":"Microsphere-assisted microscopy (MAM) is a label-free super-resolution imaging technique based on traditional optical microscopy, but the current research usually chooses reflected illumination (RI). In this work, the effects of microsphere size, refractive index, and immersion environment on the imaging properties of MAM in imaging a 300-nm-period grating sample under transmitted illumination (TI) are systematically investigated. The experimental results reveal that under TI, microspheres with a smaller size exhibit higher resolution, and microspheres with a higher refractive index show higher magnification in imaging. Under three immersion conditions (in the air, partial immersion, and full immersion in an SU-8 film), lower refractive index SiO2 microspheres (partial immersion) and higher refractive index BaTiO3 glass microspheres (full immersion) can obtain higher contrast and resolution in imaging. Despite the difference in illumination modes, the imaging properties of MAM under TI and RI are similar. Specifically, the relative refractive index between the microsphere and the surrounding environment affects the magnification, while the contrast is strongly influenced by the interfacial reflection and the relative refractive index between the microsphere and the surrounding medium. The magnification and resolution of MAM are also related to photonic nanojet (PNJ) of the microsphere. When the full width at half-maximum of the PNJ is narrow and the PNJ is close to the surface of the microsphere, it is beneficial for improving resolution. Our findings can help to reveal the underlying mechanisms of MAM and promote its practical applications.","PeriodicalId":19540,"journal":{"name":"Optics letters","volume":"50 19","pages":"6225-6228"},"PeriodicalIF":3.3,"publicationDate":"2025-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145207317","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