El Hadj Abidi, Jaime Calvo-Gallego, Alejandro Schulman, Miguel Ferrando-Bataller, Oleg V. Minin, Igor V. Minin, Jesus E. Velázquez-Pérez, Yahya Moubarak Meziani
{"title":"Spherical and Aspherical Lenses for Boosting the Performance of Terahertz Imaging Systems","authors":"El Hadj Abidi, Jaime Calvo-Gallego, Alejandro Schulman, Miguel Ferrando-Bataller, Oleg V. Minin, Igor V. Minin, Jesus E. Velázquez-Pérez, Yahya Moubarak Meziani","doi":"10.1002/adpr.202400234","DOIUrl":"10.1002/adpr.202400234","url":null,"abstract":"<p>A comprehensive study on the enhancement of terahertz (THz) detection through the terajet effect is performed using mesoscale dielectric lenses of different shapes and sizes. Polytetrafluoroethylene (PTFE) lenses, including spherical, aspherical, and cubic geometries, are fabricated and evaluated at frequencies of 0.15 and 0.3 THz. The lenses show enhanced responsivity and reduced noise-equivalent power, with performance characteristics strongly dependent on frequency and shape. Aspherical lenses achieve superior spatial resolution at 0.3 THz, characterized by the smallest spot sizes and full width at half maximum. Although with a bigger spot size, spherical lenses show an increase of responsivity signal of a factor of 1.5 with respect to the aspherical lenses at 0.3 THz. Cubic lenses, on the other hand, exhibit significant signal strength enhancement at 0.15 THz, but not at 0.3 THz. A damping of Fabry–Pérot oscillations at higher frequencies is also observed, contributing to improved spatial resolution. These results demonstrate the potential of the terajet effect to optimize THz detection systems for diverse applications, including medical imaging, security screening, and nondestructive testing. The findings provide practical guidelines for designing advanced THz systems and emphasize the importance of tailoring lens configurations to specific operational requirements.</p>","PeriodicalId":7263,"journal":{"name":"Advanced Photonics Research","volume":"6 7","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/adpr.202400234","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144573211","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Krishangi Krishna, Jieliyue Sun, Wenyu Liu, Robert H. Hurt, Kimani C. Toussaint Jr.
{"title":"Harnessing Ultrafast Optical Pulses for 3D Microfabrication by Selective Tweezing and Immobilization of Colloidal Particles in an Integrated System","authors":"Krishangi Krishna, Jieliyue Sun, Wenyu Liu, Robert H. Hurt, Kimani C. Toussaint Jr.","doi":"10.1002/adpr.202500003","DOIUrl":"10.1002/adpr.202500003","url":null,"abstract":"<p>Microfabrication using nano- to micron-sized building blocks holds a great potential for applications in next-generation electronics, optoelectronics, and advanced materials. However, traditional methods like chemical vapor deposition and molecular beam epitaxy require highly controlled environments and specialized equipment, limiting scalability and precision. To address these challenges, a single-laser platform is presented for selective tweezing and immobilization of colloids (STIC) that integrates particle manipulation, assembly, and stabilization in one system. STIC utilizes a femtosecond laser at ultra-low power for precise, contact-free optical manipulation of colloids without material damage. At higher power, the same laser enables two-photon polymerization (TPP) to immobilize colloids securely in their intended positions. Using STIC, the assembly of 3D structures from dielectric beads to patterned arrangements of transition metal dichalcogenides (TMDs e.g., MoS<sub>2</sub>) is demonstrated. Also a TPP-fabricated handle as an intermediate support is incorporated which significantly enhances the optical tweezing efficiency of TMDs. The single-laser design eliminates the need for dual-laser systems, simplifying optical alignment, reducing heat damage, and improving efficiency. Additionally, it is shown that STIC supports direct multiphoton imaging for <i>in situ</i> inspection during fabrication. This work establishes a versatile, scalable optical platform for high-precision microstructure fabrication, offering a pathway to overcome current limitations in micro- and nanomanufacturing.</p>","PeriodicalId":7263,"journal":{"name":"Advanced Photonics Research","volume":"6 5","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/adpr.202500003","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143905406","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Research Progress on Atmospheric Turbulence Perception and Correction Based on Adaptive Optics and Deep Learning","authors":"Qinghui Liu, Yihang Di, Mengmeng Zhang, Zhenbo Ren, Jianglei Di, Jianlin Zhao","doi":"10.1002/adpr.202400204","DOIUrl":"10.1002/adpr.202400204","url":null,"abstract":"<p>Atmospheric turbulence constitutes a fundamental limiting factor in astronomical observation systems and laser communication architectures. During atmospheric propagation of optical beams, dynamically evolving wavefront aberrations are inevitably induced, rendering precise turbulence characterization and mitigation critical for optimizing operational performance of terrestrial telescopes and satellite-ground optical links. Adaptive optics (AO) represents a sophisticated methodology for optical enhancement through real-time wavefront measurement and adaptive compensation of medium-induced phase distortions. Recent years have witnessed substantial advancements in AO technology, driven by synergistic progress in fundamental theories, optoelectronic devices, and computational algorithms. Furthermore, artificial intelligence-driven turbulence processing frameworks leveraging deep neural networks have emerged as a prominent research frontier, demonstrating remarkable potential in intelligent wavefront sensing and nonlinear compensation. This work presents a systematic review of atmospheric turbulence fundamentals, including theoretical formulations and AO-based mitigation strategies. Particular emphasis is placed on deep learning-enabled intelligent correction paradigms, while critical analysis is provided regarding prospective research trajectories and implementation challenges.</p>","PeriodicalId":7263,"journal":{"name":"Advanced Photonics Research","volume":"6 7","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-03-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/adpr.202400204","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144574296","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Oleg Bannik, Fedor Kovalev, Mingkai Liu, Michal Zawierta, Dilusha Silva, Lorenzo Faraone, Mariusz Martyniuk, Ilya Shadrivov
{"title":"Micromachined Double-Membrane Mechanically Tunable Metamaterial for Thermal Infrared Filtering","authors":"Oleg Bannik, Fedor Kovalev, Mingkai Liu, Michal Zawierta, Dilusha Silva, Lorenzo Faraone, Mariusz Martyniuk, Ilya Shadrivov","doi":"10.1002/adpr.202400185","DOIUrl":"10.1002/adpr.202400185","url":null,"abstract":"<p>\u0000A mechanically tunable metamaterial concept for transmissive spectral discrimination within the long-wavelength infrared (LWIR) range (8–12 μm) is proposed and validated. The metamaterial consists of a periodically perforated gold membrane that exhibits the extraordinary optical transmission (EOT) effect, combined with a parallel silicon membrane separated by an air gap. This structure acts as a band-pass filter, with its spectral position highly sensitive to the separation gap between the membranes, which influences the resonance conditions for EOT. Numerical simulations predict tunability across the entire LWIR range with a membrane displacement of just 0.5 μm. This concept is experimentally demonstrated through vertical electrostatic actuation of the silicon membrane relative to the gold layer facilitated by a micro-electromechanical systems (MEMS) approach. The measured optical transmission of the fabricated MEMS-enabled, spectrally tunable plasmonic metamaterial shows good agreement with the numerically modeled spectral filter characteristics. Further refinement of this method could pave the way for a variety of low-cost, low-power miniature devices, enhancing spectroscopy and multispectral imaging capabilities in the thermal infrared range.</p>","PeriodicalId":7263,"journal":{"name":"Advanced Photonics Research","volume":"6 5","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-03-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/adpr.202400185","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143905417","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Improving Light Outcoupling and Addressing Measurement Specifics in Perovskite Light-Emitting Diodes with Light Management Foils","authors":"Milan Kovačič, Marko Jošt, Janez Krč, Marko Topič","doi":"10.1002/adpr.202400188","DOIUrl":"10.1002/adpr.202400188","url":null,"abstract":"<p>Near-infrared perovskite light-emitting diodes (PeLEDs), with four perovskite (PK) layer thicknesses and optional micro-textured light management (LM) foil, are fabricated to evaluate their effects on light outcoupling efficiency. Devices with a 70 nm thick PK exhibit highest external quantum efficiencies (EQE), compared to those with thinner or thicker PK layers. The PK thickness influences the overall thin-film stack and, consequently, the light outcoupling. LM foils significantly improve light outcoupling across all devices, with the thickest PK layer (160 nm) benefiting the most (60% increase), while the thinnest (40 nm) sees the least improvement (30%). Measured trends align well with optical modeling results, further highlighting the impact of sample holder design and pixel position on results. Theoretical optimization of PK thickness indicates unique optimal values for devices with or without LM foils. For devices incorporating LM foils, simulations predict an optimal PK thickness of 80 nm and an EQE of 27%. In contrast, for devices without LM foils, the optimal PK thickness of 60 nm corresponds to simulated EQE of 17%. In all cases, LM foils significantly enhance light outcoupling from bottom-emitting PeLEDs while emphasizing the necessity to include LM foils in the thin-film layer stack optimization process.</p>","PeriodicalId":7263,"journal":{"name":"Advanced Photonics Research","volume":"6 7","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-03-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/adpr.202400188","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144573915","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Andrew R. Kim, Chloe F. Doiron, Fernando J. Vega, Jaeyeon Yu, Alex M. Boehm, Joseph P. Klesko, Igal Brener, Raktim Sarma, Alexander Cerjan, Taisuke Ohta
{"title":"Imaging Photonic Resonances within an All-Dielectric Metasurface via Photoelectron Emission Microscopy","authors":"Andrew R. Kim, Chloe F. Doiron, Fernando J. Vega, Jaeyeon Yu, Alex M. Boehm, Joseph P. Klesko, Igal Brener, Raktim Sarma, Alexander Cerjan, Taisuke Ohta","doi":"10.1002/adpr.202400223","DOIUrl":"10.1002/adpr.202400223","url":null,"abstract":"<p>Dielectric metasurfaces, through volume-type photonic resonances, enable precise control of light-matter interactions for applications including imaging, holography, and sensing. The application space of dielectric metasurfaces has extended from infrared to visible wavelengths by incorporating high refractive index materials, such as titanium dioxide (TiO<sub>2</sub>). Understanding the fundamental and fabrication limits for these applications requires metrology with nanoscale resolution, sensitivity to electromagnetic fields within the meta-atom volume, and far-field excitation. In this work, photoelectron emission microscopy (PEEM) is used to image field distributions of photonic resonances in a TiO<sub>2</sub> metasurface excited with far-field, visible-wavelength illumination. The local volumetric field variations within the meta-atoms are analyzed as a function of illumination angle and polarization by comparing photoelectron images to finite-difference time-domain simulations. This study determines the inelastic mean free path of very low-energy (<1 eV) photoelectrons to be 35 ± 10 nm, which is comparable to the meta-atom height thereby highlighting PEEM sensitivity to resonances within the volume. Additionally, the simulations reveal high sensitivity of PEEM images to an in-plane component of the illumination <i>k</i>-vector. These results demonstrate that photoelectron imaging with subwavelength resolution offers unique advantages for examining light-matter interactions in volume-type (as opposed to surface) photonic modes within dielectric nanophotonic structures.</p>","PeriodicalId":7263,"journal":{"name":"Advanced Photonics Research","volume":"6 6","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-03-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/adpr.202400223","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144264687","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Extraction of Inherent Amplitude Mode from a Light Beam","authors":"Zhiyang Xia, Xiaoyu Weng, Liwei Liu, Jun He, Changrui Liao, Yiping Wang, Junle Qu","doi":"10.1002/adpr.202400198","DOIUrl":"10.1002/adpr.202400198","url":null,"abstract":"<p>\u0000Mode extraction is the inverse process of the double-beam superposition principle in classical optics. While polarization mode extraction has been successfully demonstrated using an <i>m</i>-order vector vortex beam, amplitude mode extraction remains a significant challenge due to the complex intertwinement of inherent amplitude modes. To address this challenge, a method is developed to extract arbitrary amplitude modes of a light beam in both the real and imaginary domains. By introducing competition between amplitude modes in these domains, the desired amplitude modes within a light beam can be selectively extracted in the focal region of an objective lens using an optical pen. This work demonstrates the principle of amplitude mode extraction, thereby potentially paving the way for multidimensional manipulation of light fields.</p>","PeriodicalId":7263,"journal":{"name":"Advanced Photonics Research","volume":"6 7","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/adpr.202400198","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144573203","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Highly Efficient Biphoton Generation from Thin Dense Atomic Ensemble","authors":"Heewoo Kim, Hansol Jeong, Han Seb Moon","doi":"10.1002/adpr.202400214","DOIUrl":"10.1002/adpr.202400214","url":null,"abstract":"<p>Hybrid photonic quantum networks require photonic quantum states generated from different systems, such as atoms and quantum dots. Photonic quantum sources based on atomic ensembles are excellent candidates due to their brightness, low noise, and narrowband characteristics. Herein, a new platform for a highly efficient biphoton source is presented using a thin, dense atomic medium from a hot 1 mm-long chip-scale Cs atomic vapor cell. Strongly correlated bright biphotons are generated via spontaneous four-wave mixing from a dense atomic ensemble based on the 6S<sub>1/2</sub>–6P<sub>3/2</sub>–6D<sub>5/2</sub> transition of <sup>133</sup>Cs. Biphoton source achieves a detected biphoton count rate of 100 kilo-counts per second, a heralding efficiency of 15%, and a maximum normalized crosscorrelation function value of 100 between the signal and idler photons, despite the low detector efficiency of a silicon avalanche photodetector being less than 25% at 917 nm. Herein, the maximal violation of the Cauchy–Schwarz inequality by a factor greater than 10<sup>6</sup> at a pump power of 1 μW is obtained. The scheme for a highly efficient photon source is believed to be useful for scalable quantum networks.</p>","PeriodicalId":7263,"journal":{"name":"Advanced Photonics Research","volume":"6 4","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/adpr.202400214","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143762336","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Dynamic Humidity Modulation of Quasi-Bound States in the Continuum by Symmetry Breaking in Geometry and Permittivity","authors":"Ang Xu, Qiushun Zou, Hongsen Zhao, Yimin Chen, Chenjie Gu, Dandan Qiu, Xingyu Chen, Peiqing Zhang, Xiang Shen","doi":"10.1002/adpr.202400191","DOIUrl":"10.1002/adpr.202400191","url":null,"abstract":"<p>Hybrid metal-dielectric metasurfaces, exhibiting bound states in the continuum (BICs), support high-quality factor resonances and electric field confinement due to their ability to restrain radiation loss. However, the dynamic transformation between quasi-BICs and BICs in hybrid nanostructures by symmetry breaking in a multiplicity of ways remains a significant challenge. Herein, a novel humidity-modulated strategy is demonstrated, which regulates the dynamic transition from quasi-BICs to BICs based on the symmetry-breaking in geometry and permittivity for the hybrid photonic-plasmonic asymmetric gratings (HPAG), which consists of two alternating dielectric gratings deposited on an aluminum oxide and gold film. The regulatory mechanism involves the humidity-sensitive polyvinyl alcohol, which undergoes volume expansion and refractive index reduction as the relative humidity (RH) increases. Its Q-factor of a quasi-BIC in HPAG reached up to 873, primarily due to the breaking of out-of-plane symmetry. The HPAG can be used for humidity sensing with a sensitivity of up to 2.63/RH. Moreover, the humidity-modulated strategy is proven to be suitable for similar nanostructures (e.g., cylinder dimers, tetrameric cubes, and loop antennae). The results indicate that the humidity-modulated strategy is a promising approach for regulating optical characteristics and is applied in micro/nanophotonic devices, such as humidity sensors, and active components.</p>","PeriodicalId":7263,"journal":{"name":"Advanced Photonics Research","volume":"6 7","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-03-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/adpr.202400191","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144573960","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Anna Lucia Pellegrino, Francesca Lo Presti, Francesca Loschi, Adolfo Speghini, Graziella Malandrino
{"title":"Downshifting Layer of Europium-Doped NaGdF4: From the Optimization of the Sol–Gel Process to the Luminescent Properties","authors":"Anna Lucia Pellegrino, Francesca Lo Presti, Francesca Loschi, Adolfo Speghini, Graziella Malandrino","doi":"10.1002/adpr.202400153","DOIUrl":"10.1002/adpr.202400153","url":null,"abstract":"<p>\u0000The key issue for a wide application of solar energy is the possibility to establish an innovative photovoltaic technology that allows a more efficient energy conversion. In this direction, the use of additional layers in the well-established silicon-based modules represents a challenging strategy. In this context, the present work is devoted to the optimization of a downshifting (DS) system made of the NaGdF<sub>4</sub> matrix in the form of thin film as a host material for the europium-luminescent ions. The Eu-doped NaGdF<sub>4</sub> system is fabricated through a sol–gel approach starting from a mixture of Na(hfa)•tetraglyme, Gd(hfa)<sub>3</sub>•diglyme, and Eu(hfa)<sub>3</sub>•diglyme in ethanol solution. The operative parameters are finely tuned to pursue the formation of compact and polycrystalline films. Particularly, the annealing treatment, the nature of the substrate, and the doping ion percentage are the key parameters for the reproducible and selective formation of NaGdF<sub>4</sub> in the form of the beta (hexagonal) crystal structure with promising luminescent properties. Morphological, structural, and compositional features are deeply studied through field-emission scanning electron microscopy, X-ray diffraction analysis, and energy-dispersive X-ray analysis, respectively. The luminescence investigations confirm the properties of the Eu-doped NaGdF<sub>4</sub> as DS system.</p>","PeriodicalId":7263,"journal":{"name":"Advanced Photonics Research","volume":"6 5","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-03-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/adpr.202400153","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143905361","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}