ACS PhotonicsPub Date : 2025-08-25DOI: 10.1021/acsphotonics.5c00681
Stefano Gretter*, Mattia Mancinelli and Lorenzo Pavesi,
{"title":"Dynamic Analysis and Reservoir Computing Application of a Nonlinear Microring Resonator","authors":"Stefano Gretter*, Mattia Mancinelli and Lorenzo Pavesi, ","doi":"10.1021/acsphotonics.5c00681","DOIUrl":"10.1021/acsphotonics.5c00681","url":null,"abstract":"<p >A nonlinear microring resonator is governed by a set of coupled differential equations that model the dynamics of the optical field, temperature, and free carrier concentration within the resonator. These equations capture the mechanisms responsible for self-pulsing and memory effects, which are key in neuromorphic applications of microring resonators. One example is their use as nonlinear nodes in reservoir computing (RC). The dynamical state of a microring resonator is influenced by its control parameters: the input optical power and frequency. While previous studies have relied heavily on computationally intensive simulations to determine the resonator’s self-pulsing state or identify optimal control parameters for efficient optical computation, we propose a linearization and stability analysis to identify regions in the control parameter space associated with different dynamical behaviors. Using an adiabatic approximation of the cavity field of the mode, we calculated the Jacobian eigenvalues of the linearized system, which serve as reliable indicators of RC performance for specific input characteristics.</p>","PeriodicalId":23,"journal":{"name":"ACS Photonics","volume":"12 9","pages":"4956–4966"},"PeriodicalIF":6.7,"publicationDate":"2025-08-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.acs.org/doi/pdf/10.1021/acsphotonics.5c00681","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144898272","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":"Color-Programmable Micro-OLED Arrays with Self-Assembled AIE Patterns","authors":"Qiuyi Zhang, Qi Huang, Zikai Zhu, Dacheng Xia, Chenxu Sheng, Shoaib Awan, Ziyang Song, Fengxian Xie, Chunxiao Cong, Zhi-Jun Qiu, Laigui Hu* and Ran Liu*, ","doi":"10.1021/acsphotonics.5c00542","DOIUrl":"10.1021/acsphotonics.5c00542","url":null,"abstract":"<p >Although organic light-emitting diodes (OLEDs) have been widely employed in displays and flexible electronics, the implementation of micro-OLED arrays still remains a challenge due to the limitations of the mainstream fine metal mask (FMM) technology. Pixel sizes below 30 μm are typically hard to achieve in order to match the requirement (i.e., sub10 μm) of the emerging near-eye displays mainly due to the so-called “screen-door effect”. Conventional lithography used for high-resolution inorganic micro patterns cannot be directly applied owing to the instability of organic materials. Furthermore, damage-free techniques such as inkjet printing also encounter resolution limitations. Self-assembled monolayer (SAM)-assisted patterning and surface-microstructure-assisted patterning techniques, though promising, have so far only been applied to fabricate single-color micro-OLEDs. In this work, high-resolution micro-OLED arrays with dual-color emission were demonstrated using a phase-change material (PCM) or an aggregation-induced emission (AIE) material. Fabricated via the SAM-assisted patterning technique, the PCM dot array exhibits red emission in its amorphous phase and transitions to green emission upon annealing-induced crystallization. Leveraging this unique dual-color capability, micro-OLEDs with 5 μm pixels (2600 PPI) and dual-color emission were achieved after the preparation of other functional layers.</p>","PeriodicalId":23,"journal":{"name":"ACS Photonics","volume":"12 9","pages":"4932–4938"},"PeriodicalIF":6.7,"publicationDate":"2025-08-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144898304","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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}
ACS PhotonicsPub Date : 2025-08-22DOI: 10.1021/acsphotonics.5c00933
Artur Avdizhiyan, Artsiom Kazlou, Terunori Kaihara, Andrzej Stupakiewicz* and Ilya Razdolski*,
{"title":"Surface-Plasmon-Mediated Reduction in the Effective Gilbert Damping in Hybrid Photomagnetic Au/YIG:Co Bilayers","authors":"Artur Avdizhiyan, Artsiom Kazlou, Terunori Kaihara, Andrzej Stupakiewicz* and Ilya Razdolski*, ","doi":"10.1021/acsphotonics.5c00933","DOIUrl":"https://doi.org/10.1021/acsphotonics.5c00933","url":null,"abstract":"<p >We demonstrate surface plasmon-mediated control of the magnetic damping in photomagnetic Co-doped yittrium iron garnet (YIG:Co)/Au bilayers. Tuning the excitation wavelength across the surface plasmon resonance at the Au/YIG:Co interface, we observe a twofold increase of the lifetime of the magnetization precession induced by the nonthermal photomagnetic effect in YIG:Co. The damping modulation is attributed to the plasmon-mediated spin Seebeck effect. Numerical simulations corroborate this mechanism and enable further exploration of the parameter space of the Au plasmonic system. We analyze the role of the Au grating thickness and discuss the range of thicknesses where the largest spin-Seebeck-driven reduction of magnetic damping can be accompanied by strong photomagnetic excitation. These results expand our understanding of the nanophotonic methods for controlling spin dynamics in ferrimagnetic media which are promising for future applications in information recording and data storage.</p>","PeriodicalId":23,"journal":{"name":"ACS Photonics","volume":"12 9","pages":"5024–5031"},"PeriodicalIF":6.7,"publicationDate":"2025-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145094231","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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}
ACS PhotonicsPub Date : 2025-08-22DOI: 10.1021/acsphotonics.5c01482
Kateryna Domina, Tetiana Slipchenko, D.-H.-Minh Nguyen, Alexey B. Kuzmenko, Luis Martin-Moreno, Dario Bercioux and Alexey Y. Nikitin*,
{"title":"Tunable Hyperbolic Landau-Level Polaritons in Charge-Neutral Graphene Nanoribbon Metasurfaces","authors":"Kateryna Domina, Tetiana Slipchenko, D.-H.-Minh Nguyen, Alexey B. Kuzmenko, Luis Martin-Moreno, Dario Bercioux and Alexey Y. Nikitin*, ","doi":"10.1021/acsphotonics.5c01482","DOIUrl":"https://doi.org/10.1021/acsphotonics.5c01482","url":null,"abstract":"<p >Magnetized charge-neutral graphene supports collective hybrid electronic excitations─polaritons─which have a quantum origin. In contrast to polaritons in doped graphene, which arise from intraband electronic transitions, those in charge-neutral graphene originate from interband transitions between Landau levels, enabled by the applied magnetic field. Control of such quantum polaritons and shaping their wavefronts remains totally unexplored. Here, we design an artificial two-dimensional quantum material formed by charge-neutral graphene nanoribbons exposed to an external magnetic field. In such a metasurface, quantum polaritons acquire a hyperbolic dispersion. We find that the topology of the isofrequency curves of quantum hyperbolic magnetoexciton polaritons excited in this quantum material can change, so that the shape of the isofrequency curves transforms from a closed to an open one by tuning the external magnetic field strength. At the topological transition, we observe canalization phenomena, consisting of the propagation of all of the polaritonic plane waves in the continuum along the same direction when excited by a point source. From a general perspective, our fundamental findings introduce a novel type of actively tunable quantum polaritons with hyperbolic dispersion and can be further generalized to other types of quantum materials and polaritons in them. In practice, quantum hyperbolic polaritons can be used for applications related to quantum sensing and computing.</p>","PeriodicalId":23,"journal":{"name":"ACS Photonics","volume":"12 9","pages":"5264–5270"},"PeriodicalIF":6.7,"publicationDate":"2025-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145094229","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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}
ACS PhotonicsPub Date : 2025-08-19DOI: 10.1021/acsphotonics.5c00425
Maksym Rybachuk*, Bakhtiar Ali and Igor V. Litvinyuk,
{"title":"Ultrashort 30 fs Laser Photoablation for High-Precision and Damage-Free Diamond Machining","authors":"Maksym Rybachuk*, Bakhtiar Ali and Igor V. Litvinyuk, ","doi":"10.1021/acsphotonics.5c00425","DOIUrl":"https://doi.org/10.1021/acsphotonics.5c00425","url":null,"abstract":"<p >A 30 <i>fs</i>, 800 nm, 1 kHz femtosecond was used to photoablate diamond across radiant energy doses of 1–500 kJ/cm<sup>2</sup>, with fluences of 10–50 J/cm<sup>2</sup> and pulse counts from 100 to 10,000. The objective was to maximize material removal while minimizing surface roughness (<i>R</i><sub>a</sub>) by operating above the photoablation threshold. Results demonstrate that 30 <i>fs</i> laser photoablation achieves <i>R</i><sub>a</sub> < 0.1 μm, meeting both high- and ultrahigh-precision machining standards, while maintaining surface integrity and preventing heat-affected zone (HAZ) damage. At 1 kJ/cm<sup>2</sup> (10 J/cm<sup>2</sup> fluence, 100 pulses), an <i>R</i><sub>a</sub> of 0.09 μm was achieved, satisfying ultrahigh-precision criteria (<i>R</i><sub>a</sub> < 0.1 μm). Additionally, doses below 10 kJ/cm<sup>2</sup> consistently met high-precision machining requirements (<i>R</i><sub>a</sub> < 0.2 μm). Photoablation efficiency peaked below 50 kJ/cm<sup>2</sup>, after which material removal diminished, indicating nonlinear process limitations. The sp<sup>3</sup> diamond phase remained intact, as confirmed by the unchanged <i>T</i><sub>2g</sub> Raman mode at 1332 cm<sup>–1</sup>, with no detectable Raman <i>G</i> or <i>D</i> modes, confirming the absence of sp<sup>2</sup>-related graphitization, structural disorder, or nitrogen vacancy (NV) center annealing. These findings establish 30 <i>fs</i> laser processing as a high-precision, damage-free approach for diamond machining, with promising applications in NV center-containing quantum materials and advanced tooling.</p>","PeriodicalId":23,"journal":{"name":"ACS Photonics","volume":"12 9","pages":"4907–4915"},"PeriodicalIF":6.7,"publicationDate":"2025-08-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145094325","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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}
ACS PhotonicsPub Date : 2025-08-19DOI: 10.1021/acsphotonics.5c00909
Zelong Wu, Jie Cheng and Chenhao Wan*,
{"title":"Optical Data Encoding through Spatiotemporal Orbital Angular Momentum Spectral Engineering","authors":"Zelong Wu, Jie Cheng and Chenhao Wan*, ","doi":"10.1021/acsphotonics.5c00909","DOIUrl":"https://doi.org/10.1021/acsphotonics.5c00909","url":null,"abstract":"<p >Optical vortices are associated with photons carrying orbital angular momentum (OAM). Orthogonal OAM states constitute a spectrum that can be utilized for precision measurement, optical transmission, and quantum entanglement. Traditional OAM spectrum is confined to weighted superposition of spatial optical vortices with longitudinal OAM oriented in the direction of beam propagation. To fully exploit the vector nature of OAM spectrum, this work demonstrates a scheme for the generation and characterization of a spatiotemporal OAM spectrum that consists of weighted spatiotemporal optical vortices with OAM perpendicular to the propagation direction. The weight and topological charge of individual spatiotemporal vortices are accurately controlled. Spatiotemporal OAM spectra ranging from −12th to +12th orders are experimentally achieved. Subsequently, grayscale image coding and decoding are demonstrated using 8-bit spatiotemporal OAM spectra. The spatiotemporal OAM spectrum provides additional dimension of information and can be combined with conventional spatial OAM spectrum to achieve high-dimensional optical information processing.</p>","PeriodicalId":23,"journal":{"name":"ACS Photonics","volume":"12 9","pages":"5017–5023"},"PeriodicalIF":6.7,"publicationDate":"2025-08-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145094293","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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":"Meta-Waveguides for Scalable and Robust Optical Mode Manipulation on Etchless Thin Film Lithium Niobate","authors":"Mingrui Yuan, Xudong Zhou, Yongheng Jiang, Xiaoyue Ma, Huifu Xiao, Mei Xian Low, Aditya Dubey, Thach Giang Nguyen, Guanghui Ren, Arnan Mitchell and Yonghui Tian*, ","doi":"10.1021/acsphotonics.5c01470","DOIUrl":"https://doi.org/10.1021/acsphotonics.5c01470","url":null,"abstract":"<p >Meta-waveguides are a novel type of integrated optical waveguide structure that can enable refractive index manipulation by engineering photonic structures at subwavelength scales. Such meta-waveguides offer the advantage of providing flexible and highly customizable manipulation over multidimensional optical fields. Meta-waveguide-based optical mode manipulation technologies can control the spatial dimensions in optical waveguides. In contrast to traditional design strategies that are specific to certain mode orders, meta-waveguide-based technologies overcome the inherent limitations of mode order, offering more flexible scalability and robustness. Recently, a thin-film lithium niobate (TFLN) platform with its unique electro-optic properties and low material loss becomes an ideal choice for constructing integrated optoelectronic chips. By leveraging the lithium niobate’s etchless approach, meta-waveguides based on the TFLN platform enable innovative optical mode processing paradigms, significantly enhancing the transmission capabilities of optical communication systems. Here, we report a scalable on-chip optical mode manipulation system that utilizes the flexible refractive index distribution of meta-waveguides to excite arbitrary high-order optical modes. As a proof of concept, a 6-channel optical mode multiplexer is designed and experimentally demonstrated, which achieves low insertion loss (<1.9 dB) and crosstalk (<−19 dB) at 1550 nm, while exhibiting enhanced fabrication tolerance. This demonstration alleviates the scalability limitations in mode scalability for TFLN photonic devices, addressing the capacity bottleneck issues in optical signal processing, optical interconnects, and brain-inspired photonic computing.</p>","PeriodicalId":23,"journal":{"name":"ACS Photonics","volume":"12 9","pages":"5271–5282"},"PeriodicalIF":6.7,"publicationDate":"2025-08-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145094351","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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}
ACS PhotonicsPub Date : 2025-08-18DOI: 10.1021/acsphotonics.5c01149
Taejun Han, Chibuzo Onwukaeme, EunSu Jeon, Kang Ryeol Lee, SeokJae Yoo* and Björn M. Reinhard*,
{"title":"UV Circular Dichroism of Molecular Films on Plasmonic Nanostructures: A Comparative Case Study with On-Resonant Aluminum and Off-Resonant Silver Nanoparticles","authors":"Taejun Han, Chibuzo Onwukaeme, EunSu Jeon, Kang Ryeol Lee, SeokJae Yoo* and Björn M. Reinhard*, ","doi":"10.1021/acsphotonics.5c01149","DOIUrl":"10.1021/acsphotonics.5c01149","url":null,"abstract":"<p >Electronic absorption bands of important biomolecules and pharmaceutical compounds lie in the ultraviolet (UV) between 180 and 280 nm and thus in a spectral range that does not overlap with the localized surface plasmon resonances (LSPRs) of conventional gold (Au) or silver (Ag) nanoantennas. Aluminum (Al) nanostructures support resonances in UV, and there is significant interest in utilizing UV-resonant nanostructured Al substrates for enhancing the sensitivity of chiroptical spectroscopies such as circular dichroism (CD). In this study, we compare the CD of a chiral molecular film on Al and Ag substrates and evaluate the role of inherent and induced absorptive CD as well as of scattering CD in the UV. The CD signal of the test molecule 2,2′-bis(di-<i>p</i>-tolylphosphino)-1,1′-binaphthyl (Tol-BINAP) was measured on large random arrays of Al and Ag nanoparticles (NPs) generated by hole-mask colloidal lithography (HCL). Al NPs provide size-tunable quadrupole and dipole resonances overlapping with molecular absorption bands in the UV, while Ag NPs lack plasmon resonances in this range. The CD signal on the Al NP substrate was increased by up to 154% compared to Ag NP controls. Using Poynting’s theorem generalized to chiral media, we decompose the CD into scattering and absorptive components. The chiral film induces an asymmetric scattering response in resonant achiral Al nanocylinders, dominating the total CD. In contrast, the CD in off-resonant Ag nanocylinders arises from asymmetric absorption. The induced and inherent absorptive CD components have opposite signs and partially cancel each other.</p>","PeriodicalId":23,"journal":{"name":"ACS Photonics","volume":"12 9","pages":"5144–5154"},"PeriodicalIF":6.7,"publicationDate":"2025-08-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144935917","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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}
ACS PhotonicsPub Date : 2025-08-16DOI: 10.1021/acsphotonics.5c01071
Sonal Gupta, Ruchi Singh, Srashti Bhardwaj, Andrey Kuzmin, Somya Thakkur, Sonali Garg, Alexander Rzhevskii, Janakiram Vaitla, Alexander Baev, Soumik Siddhanta* and Paras N. Prasad*,
{"title":"Dramatic Enhancement of Targeted Subcellular Raman Imaging via Synergetic Nanoscale Integration of Resonance and Surface Enhanced Raman Scattering Mechanisms","authors":"Sonal Gupta, Ruchi Singh, Srashti Bhardwaj, Andrey Kuzmin, Somya Thakkur, Sonali Garg, Alexander Rzhevskii, Janakiram Vaitla, Alexander Baev, Soumik Siddhanta* and Paras N. Prasad*, ","doi":"10.1021/acsphotonics.5c01071","DOIUrl":"https://doi.org/10.1021/acsphotonics.5c01071","url":null,"abstract":"<p >Surface-enhanced resonance Raman scattering (SERRS) can boost the sensitivity of Raman bioimaging through fine-tuning of both the electronic resonance of the Raman reporter molecule and localized surface plasmon resonance (LSPR) of conjugated plasmonic nanostructures to realize cooperative amplification in the overlapping spectral region of both resonances. Here, we report on the design of an azobenzene-based resonance Raman (RR) reporter having its electronic molecular resonance in the visible wavelength region, where it can readily overlap with the LSPR band of a silver core/gold shell nanoparticle. Furthermore, the reporter molecule is practically nonemissive to minimize autofluorescence contamination of the Raman signal. The density functional theory (DFT) calculations confirm charge redistribution upon the optical excitation that produces significant resonant enhancement of the Raman line assigned to stretching of the single C–N bond. This enhancement is associated with the bonds located at both ends of the central Azo group. At the same time, our analysis of the frontier molecular orbitals suggests that stretching of C–N bonds, residing on the tertiary amine group and located in proximity to the surface of the nanoparticle, contributes to the overall cooperative amplification of Raman signal via surface-enhanced Raman scattering (SERS) mechanism. We further demonstrate that our RR reporter exhibits significant selective intracellular internalization and high contrast, high-resolution, stable Raman imaging of rat brain glioma (C6) cells. Our integrated approach to bioimaging nanotechnology highlights the importance of selective tunability of the plasmonic substrate, excitation wavelength, and electronic resonance of the molecular reporter for real-time, high-resolution, and high-contrast bioimaging and biomolecular interaction analysis with SERRS.</p>","PeriodicalId":23,"journal":{"name":"ACS Photonics","volume":"12 9","pages":"5074–5086"},"PeriodicalIF":6.7,"publicationDate":"2025-08-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145094376","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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}