Nanophotonics最新文献

{"title":"Probing Molecular Chirality via Linear Dichroism of Molecule‐Loaded Anisotropic Plasmonic Slots","authors":"EunSu Jeon,YoonYeong Ko,Seungwoo Choi,SeokJae Yoo","doi":"10.1002/nap2.70289","DOIUrl":"https://doi.org/10.1002/nap2.70289","url":null,"abstract":"ABSTRACT Conventional chiroptical spectroscopy relies on circularly polarized light (CPL), yet inherent retardance errors in CPL generation compromise signal fidelity and introduce artifacts from crosstalk with linear dichroism and birefringence. Here, we theoretically propose Chiroptical sensing via Linear dichroism of Anisotropic Plasmonic Slots (CLAPS), a CPL‐free chiroptical sensing scheme that employs two linearly polarized light (LPL) beams tilted with respect to the orientation axis of a plasmonic slot array filled with chiral analytes. Molecular optical activity perturbs the surface lattice resonance (SLR) of the array, producing a measurable reflectance difference between the two tilted LPL beams. Using an anisotropic chiral reflection model and numerical simulations, we reveal that the weak cross‐polarized reflection carrying chirality information is modulated by the strong co‐polarized response of the array. CLAPS circumvents the need for high‐purity CPL, offering a practically accessible route to trace‐level chiral molecule detection.","PeriodicalId":19027,"journal":{"name":"Nanophotonics","volume":"29 1","pages":""},"PeriodicalIF":7.5,"publicationDate":"2026-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148895936","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Decoupling Transparency and Electron Injection in Ultrathin Ag Electrodes Using an Al/MoO\u0000 3\u0000 Double Seed Layer for Transparent Quantum Dot Light‐Emitting Diodes","authors":"Yeyun Bae,Kyoungeun Lee,Kyunghoon Lee,Jaeyeop Lee,Jiyoon Oh,Jiwoong Yang,Chansu Kim,Jeongkyun Roh","doi":"10.1002/nap2.70283","DOIUrl":"https://doi.org/10.1002/nap2.70283","url":null,"abstract":"ABSTRACT There is growing interest in transparent quantum dot light‐emitting diodes (Tr‐QLEDs) for window‐type displays. For such devices, the top transparent electrode must simultaneously provide high optical transmittance, low sheet resistance, and efficient charge injection. Ultrathin Ag films are promising because of their high conductivity and transparency, but they tend to grow via the Volmer–Weber mode, resulting in poor continuity and increased resistance. Although seed layers have been widely used to improve Ag film continuity, their influence on charge injection in practical devices has received limited attention. Here, an Al/MoO 3 double seed layer is introduced, in which MoO 3 provides high transmittance and low sheet resistance, while Al enhances electron injection. This strategy enables continuous 10 nm Ag films with a transmittance of 63.48% and a sheet resistance of 7.35 Ω sq −1 . Tr‐QLEDs incorporating the Al/MoO 3 double seed layer exhibit a twofold increase in external quantum efficiency and a threefold improvement in operational lifetime compared with devices employing a MoO 3 single seed layer. Furthermore, large‐area Tr‐QLEDs are demonstrated on a 2 × 2 inch substrate, highlighting the potential of this electrode strategy for scalable transparent displays.","PeriodicalId":19027,"journal":{"name":"Nanophotonics","volume":"5 1","pages":""},"PeriodicalIF":7.5,"publicationDate":"2026-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148894087","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Photonic Integrated Circuit Platform on 3 μm Thick Silicon‐on‐Insulator and Its Application Examples","authors":"Timo Aalto,Dura Shahwar,Markku Kapulainen,Mikko Harjanne,Katherine Bryant,Somnath Paul,Päivi Heimala,Fei Sun,Jae‐Wung Lee,Ari Hokkanen","doi":"10.1002/nap2.70271","DOIUrl":"https://doi.org/10.1002/nap2.70271","url":null,"abstract":"ABSTRACT This paper gives an overview of the 3 μm SOI PIC platform and explains its unique characteristics, such as ultra‐high mode confinement, low losses, dense integration, polarization‐independent operation, small phase errors, ultra‐broadband operation, and ability to handle relatively large optical powers. Examples of monolithically integrated passive and active waveguide components are given, including couplers, wavelength (de)multiplexers, phase modulators, and Ge photodiodes. Hybrid integration and packaging possibilities are briefly addressed. As examples of potential applications, some results are provided for tunable lasers, optical beam steering, medical imaging, and RF beam steering. Ongoing and targeted developments for this PIC platform are also briefly discussed, and a comparison to some alternative PIC platforms is made. Access to this technology in VTT’s Micronova cleanroom with 200 mm wafer size is supported by process design kits and the PIXEurope pilot line.","PeriodicalId":19027,"journal":{"name":"Nanophotonics","volume":"58 1","pages":""},"PeriodicalIF":7.5,"publicationDate":"2026-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148894088","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Experimental and Computational Investigations of Surface Polaritons at Metal‐Oxide‐Semiconductor Interfaces","authors":"Humaira Zafar,Qiang Zhang,Rainer Straubinger,Ayman Rezek,Mauro Pereira,Ammar Nayfeh,Dalaver H. Anjum","doi":"10.1002/nap2.70285","DOIUrl":"https://doi.org/10.1002/nap2.70285","url":null,"abstract":"ABSTRACT Planar surface plasmon polaritons (SPPs) at metal–oxide–semiconductor (MOS) interfaces are central to plasmon‐assisted optoelectronic and tunneling devices, where ultrathin dielectrics govern field confinement and energy transfer. However, a direct link between electron energy‐loss spectroscopy (EELS) measurements and electromagnetic power dissipation at buried interfaces remains unclear. Here, we combine STEM–EELS with full‐wave electromagnetic simulations to investigate SPP excitation in planar and stacks with 10 nm dielectric spacers. Using a finite‐difference time‐domain approach, the fast electron is modeled as a broadband electromagnetic source, enabling decomposition of extinction into absorbed and scattered power and direct comparison with EEL spectra. We show that extinction is dominated by non‐radiative absorption, confirming that the observed resonances originate from SPPs confined to the buried Au–oxide interface. Increasing dielectric permittivity induces a redshift and modifies modal confinement, while losses remain Au‐dominated. Kramers–Kronig analysis and simulations further confirm dielectric dispersion effects and exponential evanescent decay across the oxide layer.","PeriodicalId":19027,"journal":{"name":"Nanophotonics","volume":"51 1","pages":""},"PeriodicalIF":7.5,"publicationDate":"2026-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148894091","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Reconfigurable Terahertz Multi‐Harmonic Dual‐Combs","authors":"Xuhong Ma,Zhiwei Qin,Xianglong Bi,Ziping Li,Wenjian Wan,Binbin Liu,Guibin Liu,Yue Pan,Yanming Lu,Hua Li","doi":"10.1002/nap2.70281","DOIUrl":"https://doi.org/10.1002/nap2.70281","url":null,"abstract":"ABSTRACT Dual‐comb spectroscopy, constructed from two frequency combs with slightly different repetition frequencies, enables real‐time and high‐precision measurements without mechanical scanning. In the terahertz (THz) spectral range, dual‐comb techniques provide a powerful tool for high‐resolution and rapid spectroscopy. Quantum cascade lasers (QCLs), owing to their compact footprint and favorable size, weight, and power (SWaP), have emerged as promising sources for THz dual‐comb systems. In QCL frequency combs, the repetition frequency generated through intrinsic four‐wave mixing is typically equal to the cavity round‐trip frequency, corresponding to the fundamental comb. Although this repetition frequency can be tuned via current and temperature control, the accessible tuning range remains limited. Recently, harmonic frequency combs, whose repetition frequencies are integer multiples of the cavity round‐trip frequency, have attracted increasing attention, offering enhanced single‐line signal‐to‐noise ratios and providing direct insight into the strong nonlinearity of QCLs. Here, we demonstrate a reconfigurable multi‐harmonic dual‐comb system realized on a single self‐detected THz QCL platform. By precisely controlling the driving current and thermal conditions, we achieve and switch between multiple dual‐comb configurations, including fundamental–fundamental, fundamental–second‐harmonic, second‐harmonic–second‐harmonic, and second‐harmonic–third‐harmonic dual‐combs. These results establish harmonic order as an additional degree of freedom for dual‐comb operation within a single laser system. The demonstrated platform enables high‐resolution and high‐sensitivity measurements while significantly simplifying the system architecture. More importantly, it reveals the pronounced intrinsic nonlinearity of THz QCLs, allowing dual‐comb generation even with weak spectral overlap. This reconfigurable multi‐band dual‐comb approach based on a single QCL opens new opportunities for compact THz spectroscopy and frequency metrology.","PeriodicalId":19027,"journal":{"name":"Nanophotonics","volume":"107 1","pages":""},"PeriodicalIF":7.5,"publicationDate":"2026-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148894089","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Radio‐Frequency Front‐End‐Free Hybrid Code‐Division and Space‐Division Wireless Multiplexing Using Space‐Time‐Coding Metasurface","authors":"Yuzhen Chen,Xiaoyi Wang,Guo‐Min Yang,Ya‐Qiu Jin","doi":"10.1002/nap2.70277","DOIUrl":"https://doi.org/10.1002/nap2.70277","url":null,"abstract":"ABSTRACT Code‐division multiplexing (CDM) is essential for supporting massive connectivity in wireless networks, but its implementation typically requires complex and costly radio‐frequency (RF) chains. This work presents a simplified wireless CDM system based on a space‐time‐coding metasurface (STCM). By modulating distinct spatial partitions of the metasurface with data streams prespread via orthogonal pseudo‐random codes, the STCM functions as a distributed parallel modulator. This architecture enables the metasurface to perform simultaneous upconversion while directing modulated reflections from multiple spatial partitions toward either shared or distinct directions. Although these data‐carrying waves may physically overlap in the far‐field, the inherent orthogonality of the spread codes ensures that the receiver can successfully decorrelate and recover each multiplexed stream. Experimental validation demonstrates three core scenarios: multistream to a single direction, distinct single‐stream to distinct directions, and multistream to multiple directions (each direction gets multiple streams), all achieved without conventional RF chains. The proposed STCM‐based hybrid CDM and space‐division multiplexing (SDM) architecture enables simultaneous multiuser communication with a radically simplified RF front‐end, paving the way for simplified, high‐capacity wireless systems for future wireless networks.","PeriodicalId":19027,"journal":{"name":"Nanophotonics","volume":"354 1","pages":""},"PeriodicalIF":7.5,"publicationDate":"2026-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148894162","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Microring Resonator Dispersion Metrology With Neural Networks","authors":"Ergun Simsek,Shao‐Chien Ou,Gregory Moille,Kartik Srinivasan","doi":"10.1002/nap2.70269","DOIUrl":"https://doi.org/10.1002/nap2.70269","url":null,"abstract":"ABSTRACT Precise knowledge of resonator dispersion, from both geometric and material contributions, is essential for reliable high‐performance nonlinear integrated photonics devices, such as optical parametric oscillators, frequency doublers, and integrated optical frequency combs. However, direct measurements at the fabrication level provide limited knowledge, whether through destructive cross‐section imaging or nondestructive ellipsometry, whereas complete optical characterization that enables precise dispersion metrology is time‐consuming and poorly suited for mass‐scale foundry fabrication. In this work, we develop a machine learning framework to solve three complementary problems: (i) predicting resonator geometric dimensions, (ii) identifying the correct material dispersion, and last, but not least, (iii) precisely reconstructing the integrated dispersion spectrum directly from ring dimensions. These three neural networks together enable both inverse and forward characterization of microring resonators. Using numerically generated datasets based on Sellmeier‐type material models, we demonstrate  nm ring dimension prediction accuracy without noise,  nm prediction accuracy with dispersion samples under a realistic frequency measurement noise level ( MHz), and 16 nm prediction accuracy at a higher noise level ( MHz). The Sellmeier model classification exceeds 99% accuracy in all cases. Importantly, dispersion sampled far from the pump resonances proves most informative, reducing full‐spectrum characterization requirements. The forward‐prediction network reconstructs dispersion spectra from the ring dimensions with high accuracy, providing a rapid alternative to numerical simulations and enabling quick assessment of the dispersion regime. Additionally, we present two experimental case studies: in the first, we demonstrate that machine learning can infer trapezoidal ring cross‐sectional geometry, including sidewall angle, from measured integrated dispersion data; in the second, we validate our approach against a publicly available dataset, where ML‐predicted width and height show close agreement with independently measured values despite an unconstrained ring radius. By combining both inverse and forward predictions, our results highlight the potential of machine learning applied to dispersion data as a rapid, nondestructive tool for wafer‐scale quality control and process monitoring in photonic foundries.","PeriodicalId":19027,"journal":{"name":"Nanophotonics","volume":"12 1","pages":""},"PeriodicalIF":7.5,"publicationDate":"2026-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148894092","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Toward Coherent Polaritonic Devices Operating at Room Temperature","authors":"Addhyaya Sharma,Ezra Bader,Ravindra K. Yadav,Juan Carlos Obeso Jureidini,Michael Reitz,Daegwang Choi,Rishabh Kaurav,Joel Yuen‐Zhou,Vinod M. Menon","doi":"10.1002/nap2.70249","DOIUrl":"https://doi.org/10.1002/nap2.70249","url":null,"abstract":"ABSTRACT Exciton–polariton condensates are a promising platform for analog computation due to their macroscopic coherence and the ability to manipulate and address them optically. Patterned structures supporting these condensates further enable the realization of coherent polaritonic circuits. However, most demonstrations have relied on conventional III–V semiconductor platforms operating at cryogenic temperatures or requiring complex fabrication methods. Here, we realize molecular polariton condensate waveguides and related structures that support coherent condensate propagation at room temperature. The platform is based on a Tamm microcavity incorporating Rhodamine 3B Perchlorate embedded in a small‐molecule ionic isolation lattice (SMILES) complex as the excitonic medium, with photonic structures defined by focused ion beam milling. Spatial and momentum‐resolved photoluminescence measurements reveal room‐temperature propagation of polariton condensates in patterned waveguides. We further investigate the condensate blueshift and finite momentum, demonstrating that the condensate remains strongly confined during propagation. As a proof of concept, we also demonstrate condensation in custom geometries, including ring waveguides, Y‐splitters, and a Mach–Zehnder interferometer. These results establish a versatile platform for the rapid prototyping of polaritonic devices and represent an important step toward complex fully integrated polaritonic circuits operating at room temperature.","PeriodicalId":19027,"journal":{"name":"Nanophotonics","volume":"1 1","pages":""},"PeriodicalIF":7.5,"publicationDate":"2026-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148894028","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mid‐Infrared on‐Chip Dichroic Filters Enabled by Adiabatic Evolution and Dispersion‐Engineered Subwavelength Grating Waveguides","authors":"Yuheng Liu,Wenchen Yin,Yuhan Sun,Lipeng Xia,Yulin Wu,Xiaochuan Xu,Yi Zou","doi":"10.1002/nap2.70279","DOIUrl":"https://doi.org/10.1002/nap2.70279","url":null,"abstract":"ABSTRACT Broadband high‐performance optical filters are fundamental building blocks for advancing mid‐infrared (MIR) integrated photonics, particularly for applications in molecular sensing and free‐space communication. Although dichroic filters offer robust high‐roll‐off performance in the near‐infrared, their realization in the critical MIR atmospheric transparency windows (3–5 μm) has remained largely unexplored. In this work, we demonstrate a high‐performance on‐chip dichroic filter on a silicon‐on‐insulator (SOI) platform, specifically engineered for the 3300–3700 nm spectral range. By integrating a longitudinally segmented subwavelength grating (SWG) waveguide, we effectively mitigate slot‐like propagation losses induced by sidewall roughness while simultaneously achieving precise control over mode dispersion. Through the synergistic adiabatic evolution and asymmetric directional coupler theory, the device achieves a maximum roll‐off rate of approximately 1 dB/nm and an extinction ratio exceeding 12 dB at a measured cut‐off wavelength of λ c  ≈ 3460 nm. The filters exhibit flat‐top low‐pass and high‐pass characteristics over a 400‐nm bandwidth with negligible insertion loss. Our results demonstrate strong agreement between theoretical analysis and experimental validation, providing a scalable solution for interchannel crosstalk suppression and high‐SNR signal extraction in MIR photonic integrated circuits. This work fills a critical gap in the MIR toolkit, paving the way for sophisticated on‐chip spectroscopic systems and robust free‐space optical links.","PeriodicalId":19027,"journal":{"name":"Nanophotonics","volume":"11 1","pages":""},"PeriodicalIF":7.5,"publicationDate":"2026-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148894257","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Misaligning Cascaded Liquid Crystal Elements for Continuously Tunable Axial Spin‐Dependent Splitting","authors":"Yougang Ke,Xinhuai Gu,Linzhou Zeng,Zhangming Hong,Jingqing Yu,Yingqun Xiao,Xinxing Zhou,Jin Li","doi":"10.1002/nap2.70270","DOIUrl":"https://doi.org/10.1002/nap2.70270","url":null,"abstract":"ABSTRACT Achieving continuous tunability and spin‐multiplexed functionality is essential for depth‐resolved imaging, yet existing approaches suffer from fixed focal lengths, transverse‐plane splitting, or inability to acquire two depth planes simultaneously. Here, we propose and experimentally demonstrate a cascaded liquid crystal Pancharatnam–Berry phase system. It comprises two phase elements and a classic convex lens, which enables continuously tunable axial spin‐dependent splitting via controlled lateral misalignment. A relative in‐plane displacement generates a spin‐dependent quadratic phase, yielding equivalent focal powers linear with displacement and opposite signs for orthogonal spins. This mechanism continuously tunes the focal lengths of left and right circularly polarized light, producing two separate foci at distinct axial positions for parallel depth acquisition. Reversing the displacement sign dynamically interchanges the two foci. Leveraging this capability, we demonstrate multiplane imaging in a single exposure, eliminating mechanical axial scanning required in traditional microscopes. An analytical model is established to quantitatively link the lateral misalignment to the two focal positions. This work establishes misalignment‐enabled axial spin splitting as a compact and efficient platform for depth‐resolved and spin‐dependent optical systems.","PeriodicalId":19027,"journal":{"name":"Nanophotonics","volume":"3 1","pages":""},"PeriodicalIF":7.5,"publicationDate":"2026-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148894258","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}