APL Photonics最新文献

{"title":"Matrix symmetry and normality in multimode fiber transport.","authors":"Shreyas Bharadwaj, Gyeong Hun Kim, Brett E Bouma, Martin Villiger","doi":"10.1063/5.0337399","DOIUrl":"10.1063/5.0337399","url":null,"abstract":"<p><p>Multimode fibers (MMFs) support high-dimensional optical transport within a compact form factor, with growing applications in biomedical imaging, telecommunications, and quantum engineering. Realizing this potential requires accurate knowledge of the fiber transmission matrix (TM); yet experimentally measured TMs are often corrupted by system-level distortions that obscure the underlying modal physics and limit wavefront control. Here, we show that the reciprocity of optical waves imposes symmetry constraints that provide self-consistency conditions for identifying and correcting such distortions. Enforcing these constraints enables improved recovery of the transported fields and allows the computational synthesis of confocal images from reflection measurements through the fiber. We further introduce matrix normality as a physically meaningful metric that quantifies the orthogonality of the propagating modes encoded in the TM. Using controlled static compression of the fiber, we demonstrate experimentally that departures from normality at a single wavelength predict a monotonic reduction in the spectral bandwidth of the principal mode basis. These results reveal a direct connection between spatial modal structure and spectral stability in MMF transport. More broadly, they establish a unified framework for understanding and controlling broadband light propagation in MMFs and complex waveguides.</p>","PeriodicalId":8198,"journal":{"name":"APL Photonics","volume":"11 9","pages":"096101"},"PeriodicalIF":5.7,"publicationDate":"2026-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13539527/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148886132","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Label-free multimodal nonlinear microscopy enabled by an optical parametric generator.","authors":"Alejandro De la Cadena, Edita Aksamitiene, Ruo-Jing Ho, Rohit Bhargava, Stephen A Boppart","doi":"10.1063/5.0331944","DOIUrl":"10.1063/5.0331944","url":null,"abstract":"<p><p>The progress and performance of nonlinear optical microscopy have been paced by breakthroughs in laser technology. Despite substantial advances, a laser source that delivers high peak power and wavelength tunability while supporting multimodal imaging in an experimentally accessible architecture remains elusive. In this contribution, we present a scheme based on an optical parametric generator (OPG). This system bypasses optical cavities and additional amplification stages, providing tunable radiation spanning over 100 nm near the 1500 nm region. We validate the capabilities of the OPG in both nonlinear spectroscopy and microscopy. Spectroscopic performance is established by acquiring coherent anti-Stokes Raman scattering (CARS) spectra of benchmark solvents, followed by narrowband and broadband CARS microscopy of intact and fresh-frozen rodent tissue specimens. In addition to CARS, this light source can also drive two-photon-mediated processes, enabling label-free multimodal imaging, a capability that we demonstrate by co-registering multiphoton autofluorescence, second-harmonic generation, and CARS from freshly excised rodent tissues. Owing to its simple and modular configuration, this design provides an adaptable and cost-effective platform for applications requiring broadband, tunable femtosecond radiation for multimodal nonlinear optical microscopy.</p>","PeriodicalId":8198,"journal":{"name":"APL Photonics","volume":"11 6","pages":"066121"},"PeriodicalIF":5.7,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13285749/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148306623","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Three-dimensional forward-scattering imaging flow cytometry system for single-cell analysis.","authors":"Minhong Zhou, Jingjing Zhao, Xinyu Chen, Zunming Zhang, Zhaoyu Lai, Ziqi Zhou, Adam de la Zerda, Yu-Hwa Lo","doi":"10.1063/5.0301435","DOIUrl":"10.1063/5.0301435","url":null,"abstract":"<p><p>Label-free single-cell 3D imaging is essential for accurate phenotyping by minimizing perturbations to native cellular states and facilitating downstream molecular analyses. Among the available modalities, 3D forward-scattering (dark-field) imaging offers the richest subcellular details but faces challenges from strong transmitted-beam interference. We present a high-throughput 3D forward-scattering imaging flow cytometry system employing optical needle-beam illumination, linear micro-mirror arrays for axial scatter detection, and spatiotemporal deconvolution algorithms. Experimental validations with microstructures, hydrogel beads, and HEK-293 cells confirm the method's capability for robust subcellular resolution at ∼400 cells/s, enabling advanced label-free cellular diagnostics and analysis. This platform enables label-free, high-content cellular analysis and is readily adaptable to integrated cell sorting and AI-driven classification, offering broad potential for biomedical research and diagnostics.</p>","PeriodicalId":8198,"journal":{"name":"APL Photonics","volume":"10 12","pages":"126115"},"PeriodicalIF":5.3,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12700570/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145754995","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"On the importance of simultaneous label-free multimodal nonlinear optical imaging for biomedical applications.","authors":"Alejandro De la Cadena, Jaena Park, Jindou Shi, Stephen A Boppart","doi":"10.1063/5.0289864","DOIUrl":"10.1063/5.0289864","url":null,"abstract":"<p><p>Label-free nonlinear microscopy offers a powerful tool for the biomedical sciences. It enables investigations of cells and tissues using signals that emerge from endogenous biomolecules and microstructures to derive contrast, thereby preserving the physiological viability and functionality of specimens. Today, the most advanced label-free nonlinear microscopes are multimodal imaging platforms that capitalize on the heterogeneity of biological specimens, capturing not one but many nonlinear signals. Thus, label-free multimodal nonlinear imaging attains a contrast palette with complementary signals, delivering data-rich images that not only allow spatial unmixing and quantification of biochemical species but also unleash the power of correlation analyses and artificial intelligence to extract further information from specimens. In this Perspective, we recap the nonlinear contrast palette and compare the two technological strategies often used to acquire multimodal nonlinear images: a sequential approach vs a simultaneous approach. We then present their strengths and weaknesses and discuss emerging computational strategies that enhance the interpretability of multimodal data.</p>","PeriodicalId":8198,"journal":{"name":"APL Photonics","volume":"10 11","pages":"110902"},"PeriodicalIF":5.7,"publicationDate":"2025-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12632184/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145585922","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Radial polarization imaging of entangled biphoton state.","authors":"Jiung Kim, Jeeseong Hwang, Martin Y Sohn","doi":"10.1063/5.0260101","DOIUrl":"10.1063/5.0260101","url":null,"abstract":"<p><p>Polarization entanglement of single photons is a key element to enable quantum 2.0 applications, such as quantum computing, quantum networks, and quantum sensing. Verification and fidelity assessment of the entanglement state are typically performed by sequential coincidence measurements with single-pixel photon detectors. Quantum imaging techniques that use single-photon imaging cameras for visualizing an entangled biphoton state and calculating Bell's inequality have been reported. Their performances are limited for practical use due to low photon flux and low speed. Here, we introduce a new approach to image polarization-entangled biphoton states using radial polarizations, which enables rapid high-performance entanglement measurement. An intensified single-photon counting camera (SPCC) captures a single image with multiple polarizations imposed by a radial wave plate, which converts a linear polarization of single photons to radial polarizations. The coincidence photon image is rapidly taken with the SPCC in the integrate-on-chip mode, which is triggered by the idler photons set at a specific polarization angle. Bell's inequality is calculated directly from four coincidence images that show polarization correlation. Our technique not only visualizes the entangled polarization state but also enables fast full Bell-type evaluation of photonic polarization entanglement. We envision that our approach may be instrumental for developing advanced polarization-entangled photon sources and polarization-entangled quantum systems, which in turn would advance fundamental research involving dynamic photon-matter interactions.</p>","PeriodicalId":8198,"journal":{"name":"APL Photonics","volume":"10 6","pages":"066111"},"PeriodicalIF":5.7,"publicationDate":"2025-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13170514/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147939921","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Three-dimensional imaging of nanoplasma by momentum-to-position mapping","authors":"Xu Han, Jiawang Guo, Xiang Huang, Hao Huang, Xianglong Fu, Kunlong Liu, Qingbin Zhang, Peixiang Lu","doi":"10.1063/5.0264265","DOIUrl":"https://doi.org/10.1063/5.0264265","url":null,"abstract":"Laser irradiated nanostructures generate nanoplasmas with ultrahigh energy densities, yet retrieving their three-dimensional (3D) spatial distribution remains challenging due to ion expansion and loss of original spatial information. In this study, we introduce a momentum-to-position mapping method to retrieve lost 3D information in position space of the ions from intense laser irradiated nanosphere, supported by ion momentum tomographic reconstruction and molecular dynamics (MD) modeling. Our results demonstrate pronounced variations in localized nanoplasma across the nanosphere surface for different irradiated intensities, providing experimental evidence for the combined action of external and internal fields on nanoplasma formation. This work represents an advanced correlation between ion emission in both momentum and position space, offering an intuitive 3D visualization of localized nanoplasma and facilitating potential applications based on nanoplasma manipulation.","PeriodicalId":8198,"journal":{"name":"APL Photonics","volume":"10 6","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147330801","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Fast and efficient Sb-based type-II phototransistors integrated on silicon.","authors":"Lining Liu, Simone Bianconi, Skyler Wheaton, Nathaniel Coirier, Farah Fahim, Hooman Mohseni","doi":"10.1063/5.0233887","DOIUrl":"10.1063/5.0233887","url":null,"abstract":"<p><p>Increasing the energy efficiency and reducing the footprint of on-chip photodetectors enable dense optical interconnects for emerging computational and sensing applications. While heterojunction phototransistors (HPTs) exhibit high energy efficiency and negligible excess noise factor, their gain-bandwidth product (GBP) has been inferior to that of avalanche photodiodes at low optical powers. Here, we demonstrate that utilizing type-II energy band alignment in an Sb-based HPT results in six times smaller junction capacitance per unit area and a significantly higher GBP at low optical powers. These type-II HPTs were scaled down to 2 <i>μ</i>m in diameter and fully integrated with photonic waveguides on silicon. Thanks to their extremely low dark current and high internal gain, these devices exhibit a GBP similar to the best avalanche devices (∼270 GHz) but with one order of magnitude better energy efficiency. Their energy consumption is about 5 fJ/bit at 3.2 Gbps, with an error rate below 10^-9 at -25 dBm optical power at 1550 nm. These features suggest new opportunities for creating highly efficient and compact optical receivers based on phototransistors with type-II band alignment.</p>","PeriodicalId":8198,"journal":{"name":"APL Photonics","volume":"10 3","pages":"036106"},"PeriodicalIF":5.7,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11892345/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143603693","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Fast axial resolution enhancement microscopy with structured illumination","authors":"Shihang Luo, Ran Gong, Mingcong Zhang, Tao Xu, Wei Ji, Lusheng Gu","doi":"10.1063/5.0239482","DOIUrl":"https://doi.org/10.1063/5.0239482","url":null,"abstract":"In this study, we introduce Fast Axial Resolution Enhancement (FARE) microscopy, which employs tilted strip illumination to achieve a near-isotropic three-dimensional resolution with three images per plane. FARE provides an imaging rate of up to 1.5 Hz for 55 × 55 × 3 μm3 with an axial resolution of ∼270 nm. Using this technique, we observed the movement of the endoplasmic reticulum in three dimensions and discovered novel patterns of mitochondrial morphological transitions and their interactions with other organelles under oxidative stress. These findings highlight the significant potential of FARE microscopy for biomedical applications.","PeriodicalId":8198,"journal":{"name":"APL Photonics","volume":"9 12","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147908986","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Impact of polarization pulling on optimal spectrometer design for stimulated Brillouin scattering microscopy.","authors":"Jake R Rosvold, Joseph B Murray, Giulia Zanini, Brandon Redding, Giuliano Scarcelli","doi":"10.1063/5.0225074","DOIUrl":"10.1063/5.0225074","url":null,"abstract":"<p><p>Brillouin spectroscopy has become an important tool for mapping the mechanical properties of biological samples. Recently, stimulated Brillouin scattering (<i>SBS</i>) measurements have emerged in this field as a promising technology for lower noise and higher speed measurements. However, further improvements are fundamentally limited by constraints on the optical power level that can be used in biological samples, which effectively caps the gain and signal-to-noise ratio (<i>SNR</i>) of <i>SBS</i> biological measurements. This limitation is compounded by practical limits on the optical probe power due to detector saturation thresholds. As a result, <i>SBS</i>-based measurements in biological samples have provided minimal improvements (in noise and imaging speed) compared with spontaneous Brillouin microscopy, despite the potential advantages of the nonlinear scattering process. Here, we consider how a <i>SBS</i> spectrometer can circumvent this fundamental trade-off in the low-gain regime by leveraging the polarization dependence of the <i>SBS</i> interaction to effectively filter the signal from the background light via the polarization pulling effect. We present an analytic model of the polarization pulling detection scheme and describe the trade-space unique to Brillouin microscopy applications. We show that an optimized receiver design could provide >25× improvement in <i>SNR</i> compared to a standard <i>SBS</i> receiver in most typical experimental conditions. We then experimentally validate this model using optical fiber as a simplified test bed. With our experimental parameters, we find that the polarization pulling scheme provides 100× higher <i>SNR</i> than a standard <i>SBS</i> receiver, enabling 100× faster measurements in the low-gain regime. Finally, we discuss the potential for this proposed spectrometer design to benefit low-gain spectroscopy applications such as Brillouin microscopy by enabling pixel dwell times as short as 10 <i>μ</i>s.</p>","PeriodicalId":8198,"journal":{"name":"APL Photonics","volume":"9 10","pages":"100807"},"PeriodicalIF":5.4,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11503528/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142493564","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mid-infrared hyperspectral microscopy with broadband 1-GHz dual frequency combs.","authors":"Peter Chang, Ragib Ishrak, Nazanin Hoghooghi, Scott Egbert, Daniel Lesko, Stephanie Swartz, Jens Biegert, Gregory B Rieker, Rohith Reddy, Scott A Diddams","doi":"10.1063/5.0225616","DOIUrl":"10.1063/5.0225616","url":null,"abstract":"<p><p>Mid-infrared microscopy is an important tool for biological analyses, allowing a direct probe of molecular bonds in their low energy landscape. In addition to the label-free extraction of spectroscopic information, the application of broadband sources can provide a third dimension of chemical specificity. However, to enable widespread deployment, mid-infrared microscopy platforms need to be compact and robust while offering high speed, broad bandwidth, and high signal-to-noise ratio. In this study, we experimentally showcase the integration of a broadband, high-repetition-rate dual-comb spectrometer (DCS) in the mid-infrared range with a scanning microscope. We employ a set of 1-GHz mid-infrared frequency combs, demonstrating their capability for high-speed and broadband hyperspectral imaging of polymers and ovarian tissue. The system covers <math><mn>1000</mn> <mspace></mspace> <msup><mrow><mtext>cm</mtext></mrow> <mrow><mo>-</mo> <mn>1</mn></mrow> </msup> </math> at <math> <msub><mrow><mi>v</mi></mrow> <mrow><mtext>c</mtext></mrow> </msub> <mo>=</mo> <mn>2941</mn> <mspace></mspace> <msup><mrow><mtext>cm</mtext></mrow> <mrow><mo>-</mo> <mn>1</mn></mrow> </msup> </math> with 12.86 kHz spectra acquisition rate and <math><mn>5</mn> <mspace></mspace> <mi>μ</mi> <mtext>m</mtext></math> spatial resolution. Taken together, our experiments and analysis elucidate the trade-off between bandwidth and speed in DCS as it relates to microscopy. This provides a roadmap for the future advancement and application of high-repetition-rate DCS hyperspectral imaging.</p>","PeriodicalId":8198,"journal":{"name":"APL Photonics","volume":"9 10","pages":""},"PeriodicalIF":5.3,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12352579/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144871051","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}