Article
Chemistry, Multidisciplinary
Yoonsoo Rho, SeokJae Yoo, Daniel B. Durham, DongJun Kang, Andrew M. Minor, Costas P. Grigoropoulos
Summary: Nonlinear optical response is a useful tool for studying the properties of materials, but its weak signal and limited reach make it difficult to probe deep-subwavelength-scale nonlinear optics. In this study, we propose a new method using an SHG-active plasmonic nanotip to achieve efficient second harmonic generation (SHG) nanoscopy. Our simulations suggest that enhancing the nonlinear response of the sample or suppressing the tip's response can lead to a high near-field SHG contrast, providing evidence of quantum mechanical nonlinear energy transfer. Furthermore, this technique can be used to study nanoscale corrosion and other physicochemical phenomena.
Article
Optics
Zelin Hao, Wenwei Liu, Zhancheng Li, Zhi Li, Guangzhou Geng, Yanchun Wang, Hua Cheng, Hammad Ahmed, Xianzhong Chen, Junjie Li, Jianguo Tian, Shuqi Chen
Summary: Metasurfaces have shown great potential in optical wave manipulation but face challenges in multidimensional manipulation of harmonic waves generated by nonlinear metasurfaces. This study presents an efficient design strategy based on the hydrodynamic model of free electron dynamics, allowing for full complex-amplitude modulation of second harmonic generation. The proposed nonlinear metasurfaces demonstrate spin-selective SHG optical vortices with independent topological charges, opening up new possibilities for nonlinear metasurface applications in optical information and multifunctional integration.
LASER & PHOTONICS REVIEWS
(2021)
Article
Materials Science, Multidisciplinary
Fan Yang, Cristian Ciraci
Summary: We present a theoretical study on second-harmonic generation from a singular metasurface, which strongly interacts with incident light and generates intense surface polarization, resulting in the generation of second-harmonic field. By using transformation optics, the calculation of nonlinear optical response is simplified, and the dependence on the incident angle is weak, making it potentially useful for all-angle harmonic generation. Furthermore, we investigate the symmetry dependence of second-harmonic generation in the far field and demonstrate an enhanced conversion efficiency under normal incidence by breaking the surface inversion symmetry.
Article
Mathematics
Yernat M. Assylbekov, Ting Zhou
Summary: In this paper, an inverse boundary value problem of electromagnetism with nonlinear Second Harmonic Generation (SHG) process is considered. The unique determination of the electromagnetic material parameters and the SHG susceptibility parameter of the medium is shown by making electromagnetic measurements on the boundary. The case of interest is when a frequency is fixed.
JOURNAL OF DIFFERENTIAL EQUATIONS
(2021)
Article
Chemistry, Multidisciplinary
Chao Wu, Xingxing Jiang, Lin Lin, Yilei Hu, Tianhui Wu, Zheshuai Lin, Zhipeng Huang, Mark G. Humphrey, Chi Zhang
Summary: The study presents the synthesis of a polar NLO vanadate Cs4V8O22 (CVO) with excellent optical properties and strong second-harmonic generation effects achieved through hydrothermal synthesis.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Materials Science, Multidisciplinary
Tingting Liu, Xinyuan Fang, Shuyuan Xiao
Summary: Engineering nonlinear optical processes in dielectric nanostructures using chalcogenide phase-change material allows for efficient tuning of second-harmonic generation processes. The nonlinear SHG signal from nanoantennas can be enhanced and modulated by optically induced Mie-type resonances and the amorphous-to-crystalline phase change in GST. By adjusting the refractive index of GST, a maximum modulation depth of up to 540% is demonstrated, showing the potential for control of optical nonlinearity and smart designing of tunable nonlinear optical devices.
Article
Chemistry, Multidisciplinary
Chenshuang Zhang, Fangrui Lin, Yong Zhang, Haozhi Yang, Danying Lin, Jun He, Changrui Liao, Xiaoyu Weng, Liwei Liu, Yiping Wang, Bin Yu, Junle Qu
Summary: MSIM-SHG is a novel approach that combines second-harmonic generation (SHG) with multifocal structured illumination microscopy (MSIM) to achieve super-resolution imaging. It has wide applications in imaging material molecules and quantifying collagen fiber alignment, showing potential for clinical diagnosis and biological research.
Article
Optics
Mathias Hedegaard Kristensen, Peter Kjaer Kristensen, Kjeld Pedersen, Esben Skovsen
Summary: This communication demonstrates a new characterization technique that combines FT spectroscopy and SHG to achieve high spectral resolution with broadband femtosecond laser pulses. By showcasing the capabilities of the method with the strong and narrow exciton resonances of ZnO, FT-SHG offers high reproducibility and resolution within the bandwidth of the input pulse.
OPTICS COMMUNICATIONS
(2021)
Article
Chemistry, Multidisciplinary
Biwei Wu, Keyi Wu, Xuefeng Sun, Weibo Wang, Jiubin Tan
Summary: This paper introduces an imaging technique based on circular dichroism second-harmonic generation (CD-SHG) to characterize the 3D distribution of KTP nanocrystals. The circular dichroism analysis can probe the orientation of KTP samples, and the research results show that the azimuthal angle is related to the excitation polarization, refractive index mismatches, and imaging depth.
FRONTIERS IN CHEMISTRY
(2022)
Article
Materials Science, Multidisciplinary
Bryson Krause, Dhananjay Mishra, Jiyang Chen, Christos Argyropoulos, Thang Hoang
Summary: This study demonstrates enhanced second-harmonic generation and second-order nonlinear exciton-polariton strong coupling response using plasmonic nanopatch antennas (NPAs), providing important insights for nonlinear control of light-matter interactions in optical engineering and information processing.
ADVANCED OPTICAL MATERIALS
(2022)
Article
Physics, Multidisciplinary
Karim Achouri, Andrei Kiselev, Olivier J. F. Martin
Summary: We present a frequency-domain modeling technique for second-order nonlinear metasurfaces, derived from the generalized sheet transition conditions (GSTCs). By extending the GSTCs to include effective nonlinear polarizations, the effective nonlinear susceptibilities of a given metasurface can be retrieved and its nonlinear scattering responses can be predicted under arbitrary illumination conditions. The proposed model can serve as a design platform for implementing complex nonlinear metasurface based applications.
NEW JOURNAL OF PHYSICS
(2022)
Article
Optics
Henri Pesonen, Atri Halder, Juha-Matti Huusko, Ari T. Friberg, Tero Setala, Jari Turunen
Summary: The spectral spatial coherence characteristics of scalar light fields in second-harmonic generation in an optically non-linear medium were numerically analyzed. The study found that increasing intensity leads to a decrease in the overall degree of coherence for both the fundamental and second-harmonic fields, with spectral density distributions and two-point coherence deviating significantly from the initial Gaussian Schell-model beams, particularly at high intensities. The results offer a method to synthesize random optical beams with desired coherence characteristics through non-linear material interaction.
Article
Chemistry, Multidisciplinary
Yovan de Coene, Stijn Jooken, Olivier Deschaume, Valerie Van Steenbergen, Pieter Vanden Berghe, Chris Van den Haute, Veerle Baekelandt, Geert Callewaert, Stijn Van Cleuvenbergen, Thierry Verbiest, Carmen Bartic, Koen Clays
Summary: In this study, it is found that endogenous second-harmonic generation (SHG) from live cells is highly sensitive to changes in transmembrane potential (TMP), indicating the potential of using SHG as a label-free read-out tool for electrogenic cells.
Article
Nanoscience & Nanotechnology
Ruiqi Wang, Fei Liang, Xin Liu, Yi Xiao, Qianqian Liu, Xian Zhang, Li-Ming Wu, Ling Chen, Fuqiang Huang
Summary: This study confirmed that the heteroanionic oxysulfide tetrahedron can achieve balanced performance in infrared nonlinear optical crystals, including strong second-harmonic generation (SHG) response, proper birefringence, and wide band gap. The anion-mixing strategy was applied to discover melilite oxysulfide as a promising IR-NLO material system. These compounds exhibited unbiased performances of proper birefringences, strong SHG responses with phase-matchable ability, wide band gaps, and large laser-induced damage thresholds. The structure tolerance of melilite offers the possibility to improve the SHG response by tuning the orbital composition and hybridization near band edges.
ACS APPLIED MATERIALS & INTERFACES
(2022)
Article
Chemistry, Multidisciplinary
Lun Qu, Lu Bai, Chunyan Jin, Qiang Liu, Wei Wu, Bofeng Gao, Juntao Li, Wei Cai, Mengxin Ren, Jingjun Xu
Summary: Metasurfaces is an intriguing framework for nonlinear optics, offering compact design and flexibility in manipulating light. However, the nonlinearity is often limited due to the short interaction lengths with light. In this study, we demonstrate a record high efficiency of second harmonic generation using LN membrane metasurfaces, significantly improving the efficiency of nonlinear metasurfaces.
Review
Biochemistry & Molecular Biology
Camilla Olianti, Francesco Giardini, Erica Lazzeri, Irene Costantini, Ludovico Silvestri, Raffaele Coppini, Elisabetta Cerbai, Francesco S. Pavone, Leonardo Sacconi
Summary: The study compared the characteristics of three different cardiac tissue clearing methods, uDISCO, CLARITY, and SHIELD, and found that each method has its pros and cons. While the CLARITY method is most suitable for imaging labeled samples in depth, it has some disadvantages in terms of tissue preservation and timings. Further research is therefore needed to find a more ideal clearing method.
PROGRESS IN BIOPHYSICS & MOLECULAR BIOLOGY
(2022)
Article
Chemistry, Analytical
Tanveer Ahmed Shaik, Enrico Baria, Xinyue Wang, Florian Korinth, Joao L. Lagarto, Christiane Hoeppener, Francesco S. Pavone, Volker Deckert, Juergen Popp, Riccardo Cicchi, Christoph Krafft
Summary: This study investigated the biochemical, structural, and biomechanical effects of genipin (GE) cross-linking on equine pericardium (EP) using optical imaging techniques and atomic force microscopy (AFM). Results showed that GE cross-linking led to a decrease in second-harmonic signal and an increase in autofluorescence, indicating changes in biochemical and structural properties. Additionally, cross-linking increased the Young's modulus of EP.
ANALYTICAL CHEMISTRY
(2022)
Article
Neurosciences
Eros Quarta, Alessandro Scaglione, Jessica Lucchesi, Leonardo Sacconi, Anna Letizia Allegra Mascaro, Francesco Saverio Pavone
Summary: This study used wide-field calcium imaging in mice to investigate the neocortical dynamics during reach-to-grasp movements. The researchers found that beyond motor regions, other areas such as the visual and retrosplenial cortices also increased their activity levels during successful reach-to-grasp movements. Functional connectivity among neocortical areas increased transiently around movement onset and decreased during movement. However, neural activity levels correlated with kinematics measures of successful reach-to-grasp movements only in sensorimotor areas.
JOURNAL OF NEUROSCIENCE
(2022)
Article
Biochemical Research Methods
Giuseppe de Vito, Lapo Turrini, Caroline Mullenbroich, Pietro Ricci, Giuseppe Sancataldo, Giacomo Mazzamuto, Natascia Tiso, Leonardo Sacconi, Duccio Fanelli, Ludovico Silvestri, Francesco Vanzi, Francesco Saverio Pavone
Summary: Light-sheet fluorescence microscopy (LSFM) allows real-time whole-brain functional imaging in zebrafish larvae. This study presents a two-photon (2P) LSFM setup for non-invasive imaging with increased imaging speed and low laser intensity. The system was used to study pharmacologically-induced acute seizures and revealed the spatial-temporal dynamics of pathological activity, including the appearance of caudo-rostral ictal waves (CRIWs).
BIOMEDICAL OPTICS EXPRESS
(2022)
Article
Chemistry, Multidisciplinary
Alice Dal Fovo, Sara Mattana, Antonina Chaban, Diego Quintero Balbas, Joao Luis Lagarto, Jana Striova, Riccardo Cicchi, Raffaella Fontana
Summary: The fluorescence analysis of materials used in artworks is often affected by various factors, leading to uncertainties in data interpretation. This study utilized fluorescence lifetime measurements combined with Raman spectroscopy to analyze different substances used as binders and coatings in artworks, providing complementary chemical information and paving the way for future in situ applications on works of art.
APPLIED SCIENCES-BASEL
(2022)
Article
Biochemistry & Molecular Biology
Sara Mattana, Alice Dal Fovo, Joao Luis Lagarto, Maria Chiara Bossuto, Vladislav Shcheslavskiy, Raffaella Fontana, Riccardo Cicchi
Summary: Non-invasive analysis of fluorescence in mixtures of binders and pigments in artworks is challenging due to overlapping emissions. Time-resolved fluorescence imaging (TRFI) was used to improve fluorescence measurements. Portable and compact fibre-based imaging setup was used to acquire fluorescence decay features of different pigments and binders. The results demonstrate the ability to distinguish different binders with the same pigment and different pigments within a common binder. This sets a framework for broader analysis of pigments and binders and potential in situ applications in paintings.
Article
Optics
Alice Dal Fovo, Sara Mattana, Marco Marchetti, Monica Anichini, Alessio Giovannelli, Enrico Baria, Raffaella Fontana, Riccardo Cicchi
Summary: This paper presents the application of combined two-photon excited fluorescence and second-harmonic generation imaging as a versatile diagnostic tool for the microcharacterization of three hardwood species. This technique enables the visualization and compositional analysis of wood microstructures, which is crucial for studying the deterioration process of wood.
Article
Biology
Giada Magni, Francesca Tatini, Gaetano De Siena, Francesco S. Pavone, Domenico Alfieri, Riccardo Cicchi, Michele Rossi, Nicoletta Murciano, Gaia Paroli, Clarice Vannucci, Ginevra Sistri, Roberto Pini, Stefano Bacci, Francesca Rossi
Summary: The study demonstrates that blue-light photobiomodulation can stimulate cellular responses and accelerate wound healing by activating mast cells.
Article
Chemistry, Multidisciplinary
Anatolii Kashchuk, Oleksandr Perederiy, Chiara Caldini, Lucia Gardini, Francesco Saverio Pavone, Anatoliy M. Negriyko, Marco Capitanio
Summary: Particle localization plays a crucial role in advanced biological techniques. This paper presents a universal method based on local gradient calculation, which provides faster and more accurate particle localization under high noise conditions, and can be applied in nanomechanical measurements and microscopy imaging.
Article
Biochemical Research Methods
Enrico Baria, Flavio Giordano, Renzo Guerrini, Chiara Caporalini, Anna Maria Buccoliero, Riccardo Cicchi, Francesco Saverio Pavone
Summary: This study explores the combined application of fluorescence, Raman and diffuse reflectance spectroscopies for the detection and classification of brain tumor and cortical dysplasia with a label-free modality. Multivariate analysis was performed to evaluate classification accuracies of these techniques-employed both in individual and multimodal configuration-obtaining high sensitivity and specificity. Multimodal optical spectroscopy allows reliably differentiating these pathologies using a non-invasive, label-free approach that is faster than the gold standard technique and does not require any tissue processing, offering the potential for the clinical translation of the technology.
BIOMEDICAL OPTICS EXPRESS
(2023)
Editorial Material
Medicine, General & Internal
Tobias Bruegmann, Leonardo Sacconi
JOURNAL OF INTERNAL MEDICINE
(2023)
Article
Optics
Lucia Gardini, Tiziano Vignolini, Valentina Curcio, Francesco Saverio Pavone, Marco Capitanio
Summary: In HILO microscopy, a highly inclined and laminated light sheet is used to reduce background fluorescence in wide-field microscopy. However, the shaping of the illumination beam and its impact on image quality still lacks understanding. In this work, a comprehensive guide to optimize beam shape and alignment in HILO is presented, along with predictions of its performance in conventional and super-resolution microscopy. A simple optical solution is proposed to reduce the inclined beam thickness and increase the number of localizations in super-resolution imaging.
Article
Clinical Neurology
Emilia Conti, Alessandro Scaglione, Giuseppe de Vito, Francesco Calugi, Maria Pasquini, Tommaso Pizzorusso, Silvestro Micera, Anna Letizia Allegra Mascaro, Francesco Saverio Pavone
Summary: The study reveals that the extension and localization of new motor representations are specific to the treatment, with most treatments promoting segregation of motor representation to the peri-infarct region. Interestingly, only the combined therapy promotes both the recovery of forelimb functionality and the rescue of spatio-temporal features of motor-related activity.
NEUROREHABILITATION AND NEURAL REPAIR
(2022)
