Currently, the average output power of single-beam optical parametric amplification (OPA) is limited to the 100-W level due to the constraints of the average power of the pump laser. OPA pumped by multiple laser beams can transfer the energy from multiple pump lasers to the same signal laser through nonlinear amplification, and it has great potential for increasing the average power of the OPA system. In this paper, a four-beam 1030-nm ∼1-ps laser-pumped OPA system using a KTA crystal is established to investigate the high-power and high-efficiency amplification operation. Signal laser output at 1.62 μm with an average power greater than 6.5 W and efficiency larger than 15% has been achieved, thereby verifying the feasibility of achieving high average power through multi-beam pumped OPA. By adjusting the non-collinear angles of each pump beam, amplification bandwidth of the signal beam can be expanded from 14.8 nm to 33.1 nm. This provides a viable solution for spectral synthesis and laser pulse compression with multi-beam pumped OPA. Additionally, two-dimension array of frequency-doubling and sum-frequency generation in the multi-beam pumped OPA system is analyzed, offering new insights into exploring complex spatiotemporal nonlinear processes.
{"title":"High-average-power 1.62-μm optical parametric amplification using four-beam pumping","authors":"Mingwei Mao, Ruiming Wang, Zhihui Yang, Yuan Tang, Yulong Tang","doi":"10.1016/j.optcom.2026.132950","DOIUrl":"10.1016/j.optcom.2026.132950","url":null,"abstract":"<div><div>Currently, the average output power of single-beam optical parametric amplification (OPA) is limited to the 100-W level due to the constraints of the average power of the pump laser. OPA pumped by multiple laser beams can transfer the energy from multiple pump lasers to the same signal laser through nonlinear amplification, and it has great potential for increasing the average power of the OPA system. In this paper, a four-beam 1030-nm ∼1-ps laser-pumped OPA system using a KTA crystal is established to investigate the high-power and high-efficiency amplification operation. Signal laser output at 1.62 μm with an average power greater than 6.5 W and efficiency larger than 15% has been achieved, thereby verifying the feasibility of achieving high average power through multi-beam pumped OPA. By adjusting the non-collinear angles of each pump beam, amplification bandwidth of the signal beam can be expanded from 14.8 nm to 33.1 nm. This provides a viable solution for spectral synthesis and laser pulse compression with multi-beam pumped OPA. Additionally, two-dimension array of frequency-doubling and sum-frequency generation in the multi-beam pumped OPA system is analyzed, offering new insights into exploring complex spatiotemporal nonlinear processes.</div></div>","PeriodicalId":19586,"journal":{"name":"Optics Communications","volume":"607 ","pages":"Article 132950"},"PeriodicalIF":2.5,"publicationDate":"2026-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146080064","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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}
Pub Date : 2026-01-21DOI: 10.1016/j.optcom.2026.132942
Xiaohui Wang , Zhiang Gao , Chenglong Jiang , Yan Hong , Shanman Cheng , Zewen Jing , Wentao Cao , Liang Xu , Xinchen Ji , Hui Zhang , Jiawei Rui , Yingxiong Song , Fufei Pang , Liyun Zhuang , Song Yang , Xiaofeng He , Yongfeng Ju , Yinshan Yu
An orbital angular momentum (OAM) has been promisingly adopted and propagated over an optical fiber by a space-division multiplexing (SDM) for enhancing the channel capacity and propagation distance, where the system performances are inevitably disturbed by various factors. Plenty of methods have been investigated for mitigating signal interruption in the OAM-based mode group (OMG) multiplexing system, which inevitably increases the cost of device, complexities and times. For mitigating the aforementioned issues, a multiple-path receiving (MPR) method is proposed by receiving two conjugated OAM modes within an OMG for demodulating the received the multiplexed OMGs. For supporting the OAM mode propagations, a weakly-coupled OAM fiber (WCOF) is fabricated, where a lower refraction index contrast (less than 1 %) between ring-core layer and cladding is achieved for reducing the propagation loss (PL) of the supported modes. A maximal PL of 0.289 dB/km in the supported four OMGs is measured by an optical time domain reflectometry, which depicts that the proposed WOCF with a low propagation loss can be potentially used for OAG-based multiplexing through a longer propagation distance. Besides, an experiment platform is also built for showing the feasibility of the proposed method. The detected intensity and interference images depict that the transmitted three OAM modes are successfully received, respectively. Moreover, a bit error rate (BER) is also adopted to evaluate the system performances with/without MPR. The measured BER results show that an improvement of 2.30/2.39/2.98 dBm for OMG1/2/3 can be achieved when the proposed MPR is employed. Moreover, the measured BERs also demonstrate that the BERs degrade as the WCOF length/data rate increases, respectively. Besides, all measured BERs are below the threshold of hard forward error correction (HFEC) at −21 dBm from 1530 nm to 1625 nm, which implies that the proposed method can be utilized in the “C + L” waveband.
{"title":"Mitigating signal interruption of OAM- and fiber-based mode group multiplexing by receiving two conjugated OAM beams within an OAM mode group","authors":"Xiaohui Wang , Zhiang Gao , Chenglong Jiang , Yan Hong , Shanman Cheng , Zewen Jing , Wentao Cao , Liang Xu , Xinchen Ji , Hui Zhang , Jiawei Rui , Yingxiong Song , Fufei Pang , Liyun Zhuang , Song Yang , Xiaofeng He , Yongfeng Ju , Yinshan Yu","doi":"10.1016/j.optcom.2026.132942","DOIUrl":"10.1016/j.optcom.2026.132942","url":null,"abstract":"<div><div>An orbital angular momentum (OAM) has been promisingly adopted and propagated over an optical fiber by a space-division multiplexing (SDM) for enhancing the channel capacity and propagation distance, where the system performances are inevitably disturbed by various factors. Plenty of methods have been investigated for mitigating signal interruption in the OAM-based mode group (OMG) multiplexing system, which inevitably increases the cost of device, complexities and times. For mitigating the aforementioned issues, a multiple-path receiving (MPR) method is proposed by receiving two conjugated OAM modes within an OMG for demodulating the received the multiplexed OMGs. For supporting the OAM mode propagations, a weakly-coupled OAM fiber (WCOF) is fabricated, where a lower refraction index contrast (less than 1 %) between ring-core layer and cladding is achieved for reducing the propagation loss (PL) of the supported modes. A maximal PL of 0.289 dB/km in the supported four OMGs is measured by an optical time domain reflectometry, which depicts that the proposed WOCF with a low propagation loss can be potentially used for OAG-based multiplexing through a longer propagation distance. Besides, an experiment platform is also built for showing the feasibility of the proposed method. The detected intensity and interference images depict that the transmitted three OAM modes are successfully received, respectively. Moreover, a bit error rate (BER) is also adopted to evaluate the system performances with/without MPR. The measured BER results show that an improvement of 2.30/2.39/2.98 dBm for OMG1/2/3 can be achieved when the proposed MPR is employed. Moreover, the measured BERs also demonstrate that the BERs degrade as the WCOF length/data rate increases, respectively. Besides, all measured BERs are below the threshold of hard forward error correction (HFEC) at −21 dBm from 1530 nm to 1625 nm, which implies that the proposed method can be utilized in the “C + L” waveband.</div></div>","PeriodicalId":19586,"journal":{"name":"Optics Communications","volume":"607 ","pages":"Article 132942"},"PeriodicalIF":2.5,"publicationDate":"2026-01-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146026027","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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}
Pub Date : 2026-01-21DOI: 10.1016/j.optcom.2026.132943
Xuan Cao , Fuxiao Xu , Zhenjia Li , Jiacheng He , Guoshuai Zhao , Guojie Tu
The demand for three-dimensional (3D) surface topography measurement of objects in modern precision manufacturing has significantly increased. Among non-contact optical measurement methods, the 3D surface topography measurement scheme based on frequency modulated continuous wave (FMCW) ranging technology exhibits notable advantages in measurement accuracy and resistance to ambient light interference. However, similar to other ranging-based schemes, this approach mostly relies on mechanical scanning, leading to a complex system structure and high manufacturing costs. To address this challenge, this study proposes a 3D surface topography measurement scheme based on a Mach-Zehnder interferometer (MZI) and array-detection FMCW, utilizing a low-cost vertical cavity surface emitting laser (VCSEL). The main practical advantage of this scheme lies in replacing mechanical scanning with array detection, which significantly simplifies the system structure and reduces manufacturing costs while maintaining high measurement performance over long distances. Experimental results demonstrate that the proposed scheme achieves a ranging accuracy of 0.0148 mm at a distance of 5 m, with a measurement range of up to 33 mm.
{"title":"Topography measurement system based on array-detection FMCW","authors":"Xuan Cao , Fuxiao Xu , Zhenjia Li , Jiacheng He , Guoshuai Zhao , Guojie Tu","doi":"10.1016/j.optcom.2026.132943","DOIUrl":"10.1016/j.optcom.2026.132943","url":null,"abstract":"<div><div>The demand for three-dimensional (3D) surface topography measurement of objects in modern precision manufacturing has significantly increased. Among non-contact optical measurement methods, the 3D surface topography measurement scheme based on frequency modulated continuous wave (FMCW) ranging technology exhibits notable advantages in measurement accuracy and resistance to ambient light interference. However, similar to other ranging-based schemes, this approach mostly relies on mechanical scanning, leading to a complex system structure and high manufacturing costs. To address this challenge, this study proposes a 3D surface topography measurement scheme based on a Mach-Zehnder interferometer (MZI) and array-detection FMCW, utilizing a low-cost vertical cavity surface emitting laser (VCSEL). The main practical advantage of this scheme lies in replacing mechanical scanning with array detection, which significantly simplifies the system structure and reduces manufacturing costs while maintaining high measurement performance over long distances. Experimental results demonstrate that the proposed scheme achieves a ranging accuracy of 0.0148 mm at a distance of 5 m, with a measurement range of up to 33 mm.</div></div>","PeriodicalId":19586,"journal":{"name":"Optics Communications","volume":"607 ","pages":"Article 132943"},"PeriodicalIF":2.5,"publicationDate":"2026-01-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146080130","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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}
Pub Date : 2026-01-21DOI: 10.1016/j.optcom.2026.132941
Jiamin Fan , Yu Qin , Tingyu Fu , Jie Zhu , Yichun Shen , Limin Xiao , Mingyi Gao
In this work, we propose a hierarchical multiplexed multiple-input multiple-output (MIMO) equalizer with adaptive compensation capabilities, synergistically integrated into a polarization-division multiplexed and probabilistically shaped 1024-QAM coherent optical transmission system. Through hierarchical progressive compensation, the architecture achieves deep synergistic compensation for polarization crosstalk, IQ gain and phase imbalance, timing skew, and residual inter-symbol interference. This architecture is experimentally validated over a 5-km double nested anti-resonant nodeless fiber link operating at 20 GBaud. The proposed equalizer effectively mitigates signal impairments and inter-channel crosstalk inherent to high-order modulation formats, while maintaining spectral efficiency. Finally, the three-stage MIMO equalizer achieves an approximately 1.2-dB improvement in optical signal-to-noise ratio sensitivity over the two-stage counterpart at the soft-decision forward error correction threshold, alongside a spectral efficiency of 16.19 bits/s/Hz.
{"title":"Hierarchical MIMO equalizer for PDM PS-1024-QAM coherent optical transmission over DNANF","authors":"Jiamin Fan , Yu Qin , Tingyu Fu , Jie Zhu , Yichun Shen , Limin Xiao , Mingyi Gao","doi":"10.1016/j.optcom.2026.132941","DOIUrl":"10.1016/j.optcom.2026.132941","url":null,"abstract":"<div><div>In this work, we propose a hierarchical multiplexed multiple-input multiple-output (MIMO) equalizer with adaptive compensation capabilities, synergistically integrated into a polarization-division multiplexed and probabilistically shaped 1024-QAM coherent optical transmission system. Through hierarchical progressive compensation, the architecture achieves deep synergistic compensation for polarization crosstalk, IQ gain and phase imbalance, timing skew, and residual inter-symbol interference. This architecture is experimentally validated over a 5-km double nested anti-resonant nodeless fiber link operating at 20 GBaud. The proposed equalizer effectively mitigates signal impairments and inter-channel crosstalk inherent to high-order modulation formats, while maintaining spectral efficiency. Finally, the three-stage MIMO equalizer achieves an approximately 1.2-dB improvement in optical signal-to-noise ratio sensitivity over the two-stage counterpart at the soft-decision forward error correction threshold, alongside a spectral efficiency of 16.19 bits/s/Hz.</div></div>","PeriodicalId":19586,"journal":{"name":"Optics Communications","volume":"607 ","pages":"Article 132941"},"PeriodicalIF":2.5,"publicationDate":"2026-01-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146080131","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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}
Pub Date : 2026-01-21DOI: 10.1016/j.optcom.2026.132925
Xiansheng Li, Jun Xin
Multimode quantum entangled states play a crucial role in quantum information processing. However, the generation of large-scale multimode quantum entanglement in the spatial degree of freedom remains a significant challenge. In this paper, we theoretically propose a scheme for generating spatial multimode entangled states through four-wave mixing processes. Our approach is based on the topology of an SU(1,1) interferometer (SUI). For an input beam with spatial modes exhibiting circular symmetry, we demonstrate that a -mode spatially entangled state can be generated by rotating the spatial modes of the beam in one arm of the SUI along the optical axis.
{"title":"Generating spatial multimode entanglement using a spatial-mode-rotated SU(1,1) interferometer: Theoretical study","authors":"Xiansheng Li, Jun Xin","doi":"10.1016/j.optcom.2026.132925","DOIUrl":"10.1016/j.optcom.2026.132925","url":null,"abstract":"<div><div>Multimode quantum entangled states play a crucial role in quantum information processing. However, the generation of large-scale multimode quantum entanglement in the spatial degree of freedom remains a significant challenge. In this paper, we theoretically propose a scheme for generating spatial multimode entangled states through four-wave mixing processes. Our approach is based on the topology of an SU(1,1) interferometer (SUI). For an input beam with <span><math><mi>n</mi></math></span> spatial modes exhibiting circular symmetry, we demonstrate that a <span><math><mrow><mn>2</mn><mi>n</mi></mrow></math></span>-mode spatially entangled state can be generated by rotating the spatial modes of the beam in one arm of the SUI along the optical axis.</div></div>","PeriodicalId":19586,"journal":{"name":"Optics Communications","volume":"607 ","pages":"Article 132925"},"PeriodicalIF":2.5,"publicationDate":"2026-01-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146080129","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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}
Pub Date : 2026-01-20DOI: 10.1016/j.optcom.2026.132917
Yonghong Wang , Zhuoyan Wang , Yanfeng Yao , Junrui Li
To address the problems of fringe merging and loss of fringe edge information during the denoising of high-density fringe patterns in digital speckle pattern interferometry (DSPI), which seriously affects the phase reconstruction and measurement precision, a hierarchical adaptive curvelet thresholding with sine-cosine transform (HACuT) is proposed in this paper. By incorporating subband-wise noise energy estimation in the curvelet domain, local statistical constraints derived from clean image curvelet coefficients, and hierarchical scale-dependent adjustment, an adaptive thresholding scheme is constructed to enable precise and robust regulation of curvelet coefficients. Moreover, a smooth thresholding function based on the hyperbolic tangent is designed to enhance denoising stability. Simulation and experimental results demonstrate that the proposed method effectively suppresses noise, preserves fringe edge integrity, and maintains high computational efficiency, confirming its practical applicability.
{"title":"Multi-scale based approach for denoising digital speckle pattern interferometry fringe patterns using curvelet thresholding","authors":"Yonghong Wang , Zhuoyan Wang , Yanfeng Yao , Junrui Li","doi":"10.1016/j.optcom.2026.132917","DOIUrl":"10.1016/j.optcom.2026.132917","url":null,"abstract":"<div><div>To address the problems of fringe merging and loss of fringe edge information during the denoising of high-density fringe patterns in digital speckle pattern interferometry (DSPI), which seriously affects the phase reconstruction and measurement precision, a hierarchical adaptive curvelet thresholding with sine-cosine transform (HACuT) is proposed in this paper. By incorporating subband-wise noise energy estimation in the curvelet domain, local statistical constraints derived from clean image curvelet coefficients, and hierarchical scale-dependent adjustment, an adaptive thresholding scheme is constructed to enable precise and robust regulation of curvelet coefficients. Moreover, a smooth thresholding function based on the hyperbolic tangent is designed to enhance denoising stability. Simulation and experimental results demonstrate that the proposed method effectively suppresses noise, preserves fringe edge integrity, and maintains high computational efficiency, confirming its practical applicability.</div></div>","PeriodicalId":19586,"journal":{"name":"Optics Communications","volume":"607 ","pages":"Article 132917"},"PeriodicalIF":2.5,"publicationDate":"2026-01-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146025930","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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}
Pub Date : 2026-01-20DOI: 10.1016/j.optcom.2026.132929
Fanmiao Meng, Weiwei Yu
and are the fundamental models in intense laser field, facilitating the investigation of attosecond electron dynamics, the observation of nuclear wave packet evolution, and the implementation of frequency-modulated high-order harmonic generation. In this work, the high-order harmonic generation dynamics of and , under terahertz field assistance and the nuclear motion, were investigated by using numerical solutions of the non-Born–Oppenheimer time-dependent Schrödinger equation. Terahertz assistance increases the peak intensity of the central electric field while maintaining the shape of the electric field, consequently significantly extending the harmonic cutoff range and generating three distinct plateau regions. Upon considering non-Born–Oppenheimer approximation, the asymmetry of the electron cloud amplifies the interaction between electrons and nuclei, the nuclear motion is relatively slow, so the nuclei remain within the Franck–Condon region. Thus, the efficiency of the harmonic is three orders of magnitude greater than that of . These findings provide new perspectives on the microscopic principles of terahertz-assisted high-order harmonic generation and clarify the impact of nuclear motion on this phenomenon.
{"title":"Investigating the effect of nuclear motion on the high-order harmonic generation efficiency of H2+ and HD+ molecules under terahertz assistance","authors":"Fanmiao Meng, Weiwei Yu","doi":"10.1016/j.optcom.2026.132929","DOIUrl":"10.1016/j.optcom.2026.132929","url":null,"abstract":"<div><div><span><math><msubsup><mrow><mi>H</mi></mrow><mrow><mn>2</mn></mrow><mrow><mo>+</mo></mrow></msubsup></math></span> and <span><math><msup><mrow><mi>HD</mi></mrow><mrow><mo>+</mo></mrow></msup></math></span> are the fundamental models in intense laser field, facilitating the investigation of attosecond electron dynamics, the observation of nuclear wave packet evolution, and the implementation of frequency-modulated high-order harmonic generation. In this work, the high-order harmonic generation dynamics of <span><math><msubsup><mrow><mi>H</mi></mrow><mrow><mn>2</mn></mrow><mrow><mo>+</mo></mrow></msubsup></math></span> and <span><math><msup><mrow><mi>HD</mi></mrow><mrow><mo>+</mo></mrow></msup></math></span>, under terahertz field assistance and the nuclear motion, were investigated by using numerical solutions of the non-Born–Oppenheimer time-dependent Schrödinger equation. Terahertz assistance increases the peak intensity of the central electric field while maintaining the shape of the electric field, consequently significantly extending the harmonic cutoff range and generating three distinct plateau regions. Upon considering non-Born–Oppenheimer approximation, the asymmetry of the electron cloud amplifies the interaction between electrons and nuclei, the nuclear motion is relatively slow, so the nuclei remain within the Franck–Condon region. Thus, the efficiency of the <span><math><msubsup><mrow><mi>H</mi></mrow><mrow><mn>2</mn></mrow><mrow><mo>+</mo></mrow></msubsup></math></span> harmonic is three orders of magnitude greater than that of <span><math><msup><mrow><mi>HD</mi></mrow><mrow><mo>+</mo></mrow></msup></math></span>. These findings provide new perspectives on the microscopic principles of terahertz-assisted high-order harmonic generation and clarify the impact of nuclear motion on this phenomenon.</div></div>","PeriodicalId":19586,"journal":{"name":"Optics Communications","volume":"607 ","pages":"Article 132929"},"PeriodicalIF":2.5,"publicationDate":"2026-01-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146026029","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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}
Pub Date : 2026-01-20DOI: 10.1016/j.optcom.2026.132940
Yu E. Geints
Quantum dot superparticles are a specific class of metamaterials created through the self-assembly of nanometer semiconductor quantum dots into organized micro-scale structures, such as microspheres. Superparticles exhibit unique optical, chemical, and electronic properties. These properties are not merely the sum of the constituent quantum dots but rather bear the signature of the collective behavior of the nanoscale building blocks. In particular, assembling an ensemble of quantum dots into a super-sphere allows them to function as a single, high-quality optical resonator. This structure efficiently confines the emission from the pump-excited quantum dots via whispering gallery modes. The emissive properties of such a superparticle resonator remain an area of active investigation. Using numerical simulation, we study the angular structure of the photoluminescence from superparticles of various sizes and architectures formed from CdS quantum dots. We show that, in general, the angular distribution of the SP emission is characterized by strong asymmetry, with a maximum in the backward direction relative to the incident pump beam. In contrast, this asymmetry is virtually absent in the forward and side-scattering directions. The excitation of resonant modes in the superparticle enhances the emission intensity and reduces the degree of its backward asymmetry. Furthermore, coating the CdS quantum dot particle with a silicon dioxide layer increases the probability of exciting field resonances in such a core-shell superparticle.
{"title":"Angular patterns of photoluminescence in quantum dot spherical superparticles mediated by whispering-gallery modes","authors":"Yu E. Geints","doi":"10.1016/j.optcom.2026.132940","DOIUrl":"10.1016/j.optcom.2026.132940","url":null,"abstract":"<div><div>Quantum dot superparticles are a specific class of metamaterials created through the self-assembly of nanometer semiconductor quantum dots into organized micro-scale structures, such as microspheres. Superparticles exhibit unique optical, chemical, and electronic properties. These properties are not merely the sum of the constituent quantum dots but rather bear the signature of the collective behavior of the nanoscale building blocks. In particular, assembling an ensemble of quantum dots into a super-sphere allows them to function as a single, high-quality optical resonator. This structure efficiently confines the emission from the pump-excited quantum dots via whispering gallery modes. The emissive properties of such a superparticle resonator remain an area of active investigation. Using numerical simulation, we study the angular structure of the photoluminescence from superparticles of various sizes and architectures formed from CdS quantum dots. We show that, in general, the angular distribution of the SP emission is characterized by strong asymmetry, with a maximum in the backward direction relative to the incident pump beam. In contrast, this asymmetry is virtually absent in the forward and side-scattering directions. The excitation of resonant modes in the superparticle enhances the emission intensity and reduces the degree of its backward asymmetry. Furthermore, coating the CdS quantum dot particle with a silicon dioxide layer increases the probability of exciting field resonances in such a core-shell superparticle.</div></div>","PeriodicalId":19586,"journal":{"name":"Optics Communications","volume":"607 ","pages":"Article 132940"},"PeriodicalIF":2.5,"publicationDate":"2026-01-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146025928","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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}
Optical tweezers have been widely used for manipulating micro- and nanoparticles, yet conventional trapping systems often demand high optical power and complex focusing configurations. In this work, a low-power optical trapping approach is proposed using an all-dielectric slotted dimer metasurface that supports anapole-enhanced near fields. By taking advantage of the non-radiative interference between electric and toroidal dipoles, strong field confinement and steep intensity gradients are obtained, significantly enhancing the optical gradient force. Numerical simulations confirm that 20 nm-radius nanoparticles can be stably trapped at a power density of 120 μW/μm2, about one order of magnitude lower than conventional schemes. These findings reveal the physical mechanism of anapole-assisted trapping and offer a promising route for low-power, thermally stable optical manipulation.
{"title":"Anapole-enhanced local fields for low-power optical trapping in all-dielectric metasurfaces","authors":"Yewen Mei, Junqiao Wang, Qiaoqiao Wang, Mengsha Xue, Jiangnan He, Jinyuan Yang","doi":"10.1016/j.optcom.2026.132938","DOIUrl":"10.1016/j.optcom.2026.132938","url":null,"abstract":"<div><div>Optical tweezers have been widely used for manipulating micro- and nanoparticles, yet conventional trapping systems often demand high optical power and complex focusing configurations. In this work, a low-power optical trapping approach is proposed using an all-dielectric slotted dimer metasurface that supports anapole-enhanced near fields. By taking advantage of the non-radiative interference between electric and toroidal dipoles, strong field confinement and steep intensity gradients are obtained, significantly enhancing the optical gradient force. Numerical simulations confirm that 20 nm-radius nanoparticles can be stably trapped at a power density of 120 μW/μm<sup>2</sup>, about one order of magnitude lower than conventional schemes. These findings reveal the physical mechanism of anapole-assisted trapping and offer a promising route for low-power, thermally stable optical manipulation.</div></div>","PeriodicalId":19586,"journal":{"name":"Optics Communications","volume":"607 ","pages":"Article 132938"},"PeriodicalIF":2.5,"publicationDate":"2026-01-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146026022","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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}
Pub Date : 2026-01-20DOI: 10.1016/j.optcom.2026.132937
Yunfeng Li , Eneko Lopez , Jaione Etxebarria-Elezgarai , Andreas Seifert
Accurate laser beam profiling is the basis for alignment, focusing, and power delivery, but measurements are often distorted by finite apertures, limited axial scanning, and hardware limitations. We present a pinhole + single-pixel method for Gaussian beam profiling that combines multi-plane fitting of the propagation radius with an explicit finite-aperture model and a regularized, band-limited deconvolution. By fitting the beam propagation curve to measured beam radii along many axial positions, robust estimates of the beam waist and its position are obtained, avoiding bias caused by approaches that only consider divergence angle measurements. An operational rule based on the waist-to-aperture ratio indicates when convolution bias is negligible and when safeguarded deconvolution without 4 undershoot is beneficial. The workflow supports free-space and lens-assisted configurations with uncertainty propagation, is wavelength-agnostic via detector substitution, and remains cost-effective.
{"title":"Accurate and low-cost Gaussian beam profiling with pinhole and single-pixel detector","authors":"Yunfeng Li , Eneko Lopez , Jaione Etxebarria-Elezgarai , Andreas Seifert","doi":"10.1016/j.optcom.2026.132937","DOIUrl":"10.1016/j.optcom.2026.132937","url":null,"abstract":"<div><div>Accurate laser beam profiling is the basis for alignment, focusing, and power delivery, but measurements are often distorted by finite apertures, limited axial scanning, and hardware limitations. We present a pinhole<!--> <!-->+<!--> <!-->single-pixel method for Gaussian beam profiling that combines multi-plane fitting of the propagation radius with an explicit finite-aperture model and a regularized, band-limited deconvolution. By fitting the beam propagation curve to measured beam radii along many axial positions, robust estimates of the beam waist and its position are obtained, avoiding bias caused by approaches that only consider divergence angle measurements. An operational rule based on the waist-to-aperture ratio <span><math><mrow><msub><mrow><mi>w</mi></mrow><mrow><mn>0</mn></mrow></msub><mo>/</mo><mi>d</mi></mrow></math></span> indicates when convolution bias is negligible and when safeguarded deconvolution without 4<span><math><mi>σ</mi></math></span> undershoot is beneficial. The workflow supports free-space and lens-assisted configurations with uncertainty propagation, is wavelength-agnostic via detector substitution, and remains cost-effective.</div></div>","PeriodicalId":19586,"journal":{"name":"Optics Communications","volume":"607 ","pages":"Article 132937"},"PeriodicalIF":2.5,"publicationDate":"2026-01-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146026024","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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}
扫码关注我们
求助内容：
应助结果提醒方式：
京公网安备 11010802042870号