ACS Photonics最新文献

{"title":"Quasi-Two-Dimensional CsPbBr3 Quantum Dot Superlattice/WS2 Hybrid Photodetector: Self-Assembly Fabrication and Performance Optimization","authors":"Huanteng Luo, Yiming Zhao, Zhenjun Chen, Yao Zhou, Jiabin Li, Zheng Liu, Jie Zhao, Tao Zheng, Wei Gao, Xiao Liu","doi":"10.1021/acsphotonics.4c02218","DOIUrl":"https://doi.org/10.1021/acsphotonics.4c02218","url":null,"abstract":"The field of optoelectronics has witnessed a surge of interest in hybrid structures that combine colloidal quantum dots (QDs) and two-dimensional (2D) materials. These structures are expected to offer a synergistic blend of high responsivity and rapid response times. However, the potential of QD-based photodetectors has been consistently undermined by the limited carrier mobility in QD films, which arises from the inherent disordered QD and ligand packing produced through conventional fabrication methods. It introduces a pioneering approach to address this limitation: the successful growth and lossless transfer of a micrometer-scale mesocrystalline, oriented packed CsPbBr₃ QD superlattice (SL) onto 2D WS₂. The effective coupling within these SLs endows them with quasi-2D material characteristics and, when integrated with the intrinsic 2D properties of WS₂, results in a photodetector with exceptional performance. Under 405 nm illumination, it demonstrates a remarkable responsivity of 91.24 A/W, a specific detectivity of 1.15 × 10¹¹ Jones, and swift response times of 160 μs/380 μs. These performance metrics exceed those of disordered CsPbBr₃ QDs/WS₂ photodetector prepared by spin-coating, underscoring the superior optoelectronic properties of the SL/WS₂ hybrid structure. This breakthrough not only contributes to the design of high-performance photodetectors but also facilitates transformative progress in the field of optoelectronic technologies.","PeriodicalId":23,"journal":{"name":"ACS Photonics","volume":"24 1","pages":""},"PeriodicalIF":7.0,"publicationDate":"2025-01-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143031318","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":"Anomalous Lasing Behavior in a Nonlinear Plasmonic Random Laser","authors":"Renu Yadav, Sourabh Pal, Subhajit Jana, Samit K. Ray, Maruthi M. Brundavanam, Shivakiran Bhaktha B. N","doi":"10.1021/acsphotonics.4c01578","DOIUrl":"https://doi.org/10.1021/acsphotonics.4c01578","url":null,"abstract":"Plasmonic random lasers involve the interaction of emitters and metallic scatterers in extremely small mode volumes, which give rise to interesting nonlinear optical phenomena in random nanocavities. Here, we present an anomalous lasing behavior in a plasmonic random laser composed of vertically standing ZnO nanorods decorated with Au nanoislands and infiltrated with a dye-doped polymer matrix. The coupling of random laser modes to plasmonic nanocavities with high absorption losses results in unusual lasing behavior. At higher pump fluences, the nonlinear optical behavior of the Au nanoislands induces a second kink in the threshold characteristics. Various statistical tools have been employed to analyze the intensity fluctuations of the random laser modes, validating this unique lasing behavior.","PeriodicalId":23,"journal":{"name":"ACS Photonics","volume":"15 1","pages":""},"PeriodicalIF":7.0,"publicationDate":"2025-01-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143031317","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":"Highly Resistive Semitransparent G–aSi–ITO Photodetectors with Graded Energy Band Gaps","authors":"Jiyoun Jeong, Minho Choi, Jaewu Choi","doi":"10.1021/acsphotonics.4c01562","DOIUrl":"https://doi.org/10.1021/acsphotonics.4c01562","url":null,"abstract":"Nonhydrogenated, undoped semitransparent amorphous silicon thin films exhibit a thickness-dependent Tauc optical energy band gap and form uniquely highly resistive devices with a graded energy band gap. When combined with optically transparent, electrically conductive, and flexible graphene, these highly resistive semitransparent amorphous silicon films with graded energy band gaps offer significant potential for the development of graphene (G)–amorphous silicon (aSi: nonhydrogenated and undoped)–indium tin oxide (ITO) photodetector arrays fabricated on glass. These arrays are promising for future semitransparent optoelectronic applications, such as sensors in displays and see-through or video-through augmented reality (AR)/virtual reality (VR) glasses. Notably, these structures exhibit unique junction characteristics, with the Fermi level pinned at bulk defect states, as well as distinctive photoresponse properties.","PeriodicalId":23,"journal":{"name":"ACS Photonics","volume":"13 1","pages":""},"PeriodicalIF":7.0,"publicationDate":"2025-01-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143026624","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":"Enhanced Speed and Tunability of Liquid Crystals in Nanocavities via Engineering the Local Electromagnetic Field","authors":"Abu Aisheh Majd, C. K Amaljith, Abdulhalim Ibrahim","doi":"10.1021/acsphotonics.4c01916","DOIUrl":"https://doi.org/10.1021/acsphotonics.4c01916","url":null,"abstract":"The speed of nematic liquid crystals (LCs) is usually limited by the viscoelastic relaxation time, determined by the viscosity, elastic constant, and device thickness. Here, we demonstrate breaking this limit by confining the LC in a resonant nanocavity and designing the electromagnetic field to be concentrated within a specific region of the LC where the molecules react strongly to the applied voltage. Confining the LC within a subwavelength deep silicon (Si) grating of 712 nm height and 566 nm space, we achieve a guided mode resonance that results in high field confinement at the center of the LC space at the resonance wavelength. Conversely, outside the resonance wavelength, the field confinement shifts to the Si lines. This configuration reduces the rise time by an order of magnitude, from 2 ms to 200 μs at the resonance wavelength. The optimized field overlap integral at the center of the LC space indicates that most of the light–matter interactions occur in this region. As a result, this central region responds faster to an increasing voltage than does the entire LC region, thereby explaining the faster response observed at resonance. Similarly, the tunability in response to voltage and temperature can be enhanced if the alignment inside the nanocavities is better controlled. This method paves the way for ultrafast devices that utilize faster LC modes and innovative resonant nanocavity designs.","PeriodicalId":23,"journal":{"name":"ACS Photonics","volume":"74 1","pages":""},"PeriodicalIF":7.0,"publicationDate":"2025-01-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143020058","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":"Brain-Like Device Simulating Dendrites Perception Process and Optical Induced Excitatory Postsynaptic Current","authors":"Jia-Ying Chen, Wen-Min Zhong, Qi-Zhong Ren, Ang He, Xiao-Bin Guo, Yan-Ping Jiang, Qiu-Xiang Liu, Xin-Gui Tang","doi":"10.1021/acsphotonics.4c01535","DOIUrl":"https://doi.org/10.1021/acsphotonics.4c01535","url":null,"abstract":"The traditional von Neumann computing architecture leads to hidden costs in terms of computing resources and energy demand, and the brain-inspired neuromorphic artificial intelligence architecture is receiving increasing attention as one of the main competitors in improving computing power. Based on the issues above, a brain-like device based on Mg_0.1Zn_0.9O thin film is fabricated. This device can simulate various synaptic behaviors, including typical long/short-term plasticity. In neuromorphic computing, an artificial neural network is built to achieve handwritten digit recognition. The accuracy of recognition was improved through the nonlinearity modulation of synaptic weights (conductance). The brain-like device simulated dendrite sensing processes and exhibits four behavioral outcomes. Excitatory postsynaptic current (EPSC) is induced by 365 nm ultraviolet stimulation with an intensity of 23.5 mW/cm² on the brain-like device. The memory effect of EPSC is modulated through changing the duration of light, which is similar to the learning process of the human brain and shows potential in optical neuromorphic devices.","PeriodicalId":23,"journal":{"name":"ACS Photonics","volume":"105 1","pages":""},"PeriodicalIF":7.0,"publicationDate":"2025-01-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143020022","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":"Comment on “Synthesis and Direct Sampling of Single-Cycle Light Transients by Electron Tunneling in a Nanodevice”","authors":"Phillip D. Keathley, Felix Ritzkowsky","doi":"10.1021/acsphotonics.4c01800","DOIUrl":"https://doi.org/10.1021/acsphotonics.4c01800","url":null,"abstract":"A recent article by Luo et al., “Synthesis and Direct Sampling of Single-Cycle Light Transients by Electron Tunneling in a Nanodevice.” <i>ACS Photonics</i> <b>2023</b>, <i>10</i>, 2866–2873, describes the use of photoassisted tunneling from nanostructures to sample synthesized optical field transients in the time domain. The authors claim that with their measurement approach the single-photon absorption process they used for detection is sufficient for the complete characterization of the measured optical field transients in the time domain, thus providing complete amplitude and phase information in the frequency domain. However, our own analysis shows that if the experiments described in the manuscript behave in the way the authors describe, it would in fact not be possible to retrieve complete optical field information. Our analysis finds that measurements described by the authors should only provide spectral amplitude information no different from the information provided by a spectrometer. As a result of our findings, we have significant concerns regarding the validity of the key claims of the paper.","PeriodicalId":23,"journal":{"name":"ACS Photonics","volume":"137 1","pages":""},"PeriodicalIF":7.0,"publicationDate":"2025-01-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143020026","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":"Suppressing Metal Cation Diffusion in Perovskite Light-Emitting Diodes via Blending Amino Acids with PEDOT:PSS","authors":"Joonseok Kim, Min-Gi Jeon, Subin Yun, Artavazd Kirakosyan, Jihoon Choi","doi":"10.1021/acsphotonics.4c02027","DOIUrl":"https://doi.org/10.1021/acsphotonics.4c02027","url":null,"abstract":"While the migration of halide anions in the perovskite lattice has been extensively studied owing to the undesirable shifts in the emission spectrum of perovskite light-emitting diodes (PeLEDs), the diffusion behavior of doped metal cations in perovskite crystals during device operation remains hitherto unexplored. Therefore, gaining a deep understanding and developing mitigation strategies for ion migration are crucial to achieving the full potential of the PeLED technology. In this study, we analyzed the feasibility of using of amino acids as interlayer additives in poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) to block metal cation migration and passivate surface defects in Na⁺-doped CsPbBr₃ films. We systematically selected and analyzed a series of amino acids (<span>l</span>-leucine, <span>l</span>-lysine, and <span>l</span>-glutamine) and found that blending PEDOT:PSS with <span>l</span>-lysine significantly suppressed Na⁺ diffusion and enhanced the external quantum efficiency (EQE) of the CsPbBr₃ PeLEDs. This result was attributed to the chelating ability of <span>l</span>-lysine with amine and carboxyl groups, which form strong coordination bonds with the metal cations. Furthermore, the <span>l</span>-lysine with two amine groups improved the crystallization quality of CsPbBr₃ films with reduced surface roughness and improved surface passivation, leading to increased photoluminescence quantum yields. Overall, the modified CsPbBr₃ PeLEDs with <span>l</span>-lysine-blended PEDOT:PSS exhibited much improved device performance, such as EQE and luminance. Our results provide insights into the role of amino acid additives in enhancing the performances and stabilities of perovskite-based optoelectronic devices.","PeriodicalId":23,"journal":{"name":"ACS Photonics","volume":"74 1","pages":""},"PeriodicalIF":7.0,"publicationDate":"2025-01-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143026674","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":"Tantalum Pentoxide Integrated Photonics: A Promising Platform for Low-Loss Planar Lightwave Circuits with Low Thermo-Optic Coefficients","authors":"Zhenyu Liu, Wenle Yao, Mingjian You, Xiaolun Yu, Ning Ding, Weiren Cheng, Zhengqi Li, Xingyu Tang, Fei Guo, Dan Lu, Qiancheng Zhao","doi":"10.1021/acsphotonics.4c01485","DOIUrl":"https://doi.org/10.1021/acsphotonics.4c01485","url":null,"abstract":"Photonic integrated external laser cavities are transformative components in laser frequency stabilization and linewidth narrowing applications. A key challenge in contemporary photonic integration is to realize low-loss waveguides while balancing the thermo-optic response of the cavities. Tantalum pentoxide (Ta₂O₅) has emerged as a promising photonic platform due to its low thermo-optic coefficient (TOC) and low material loss. Incorporating Ta₂O₅/SiO₂ waveguides into a photonic circuit requires trade-offs among waveguide loss, device footprints, thermorefractive noise, optical I/O efficiency, and other desired functionalities. In this work, we present a Ta₂O₅ photonic platform that emphasizes low propagation loss and low thermo-optic sensitivity. We demonstrate that the intrinsic <i>Q</i> factors of these resonators exceed 10⁶, corresponding to a propagation loss of 0.27 dB/cm at 1550 nm, using our CMOS-compatible fabrication technique. The temperature-dependent wavelength shift (TDWS) of the Ta₂O₅ resonators is merely 9 pm/K. The thermorefractive frequency noise of the Ta₂O₅ microresonators is predicted to be half smaller than that of Si₃N₄ resonators. Several key building blocks of integrated external laser cavities were demonstrated, including high-<i>Q</i> resonators, self-coupled microresonators, Vernier ring resonators, Sagnac loop mirrors, edge couplers, and Y-branch splitters, which contribute to a comprehensive suite of planar lightwave components on the Ta₂O₅ platform. A narrow-linewidth hybrid-integrated laser has been demonstrated, utilizing a distributed feedback (DFB) laser diode self-injection locked to a Ta₂O₅ microresonator. A fundamental linewidth of 1.6 kHz has been obtained. The distinctive optical characteristics of the Ta₂O₅ waveguides could have a broader impact on high-capacity, temperature-robust, and multifunctional photonic integrated circuits, which are essential for the next-generation photonic computing systems, quantum photonic circuits, and beyond.","PeriodicalId":23,"journal":{"name":"ACS Photonics","volume":"28 1","pages":""},"PeriodicalIF":7.0,"publicationDate":"2025-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142992632","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":"High-Efficiency and Flat-Top Electro-Optic Frequency Comb Using a Single Modulator and Drive on Thin-Film Lithium Niobate","authors":"Gengxin Chen, Ziliang Ruan, Liu Liu","doi":"10.1021/acsphotonics.4c01688","DOIUrl":"https://doi.org/10.1021/acsphotonics.4c01688","url":null,"abstract":"Optical frequency comb sources are essential components for applications in high-capacity optical communication, large-scale optical computing systems, and high-precision laser-based light detection and ranging. These applications require high-performance, flexible, and easy-to-operate chip-scale integrated frequency comb generators featuring good spectral flatness and high efficiency. Here, we demonstrate a new design strategy to achieve flat-top electro-optic frequency combs on the thin-film lithium niobate platform using a hybrid-mode Mach–Zehnder modulator structure. The proposed device adopts only a single modulator and a single microwave source, greatly reducing the overhead on the microwave components as well as the operation of the device. The fabricated device shows a low optical loss of ∼0.2 dB, a tunable central wavelength up to a range of ∼80 nm, a flexible frequency spacing from 18 to 38 GHz, and a wide 5 dB flat-top optical bandwidth of ∼6.38 nm. A double-pass configuration with a compact footprint of 0.745 × 0.07 cm is also introduced to fully exploit the coplanar microwave waveguide on the chip. A similar comb performance is obtained using this device, showing a doubled efficiency for comb generations.","PeriodicalId":23,"journal":{"name":"ACS Photonics","volume":"15 1","pages":""},"PeriodicalIF":7.0,"publicationDate":"2025-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142992633","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":"Reply to Comment on “Synthesis and Direct Sampling of Single-Cycle Light Transients by Electron Tunneling in a Nanodevice”","authors":"Yang Luo, Alberto Martin-Jimenez, Frank Neubrech, Na Liu, Manish Garg","doi":"10.1021/acsphotonics.4c02139","DOIUrl":"https://doi.org/10.1021/acsphotonics.4c02139","url":null,"abstract":"The phase in the lock-in detection, as derived in the discussions above, is (<i>f</i>₁ + <i>f</i>₀)τ – ϕ′′τ² + ϕ′′′τ³. Please note that the GDD (ϕ′′) appears with an opposite sign to both the linear phase term as well as to the second order chirp (ϕ′′′). Thus, an increase of dispersion (positive linear chirp, ϕ′′), will have an inverse effect on the temporal profiles of the laser-induced tunnelling current. The phase characterized in our experiments will also have the contribution of the dispersive phase profile of the localized surface plasmon resonance (LSPR) of the nanodevice, as also demonstrated in the following work: <i>Nature Photonics</i> <b>2021</b>, <i>15</i>, 456–460. Figure 1. Characterization of dispersion by the frequency modulation technique. (a) Comparison of the temporal profiles of the laser-induced tunnelling current measured at the lock-in frequency of <i>f</i>₀ when the laser pulses traverses though no glass (black curve) and ∼2 mm thick fused silica glass (blue curve). The dispersive element is placed in the path of the laser beam before it enters the interferometric setup. (b) Comparison of the spectrum of the incident laser pulses on the device (green curve) with the spectra of the laser pulses as retrieved by the Fourier-transformation of the temporal profiles shown in (a). (c) Comparison of the spectral phases of the laser pulse which traverses through the glass (blue curve) with the laser pulse which does not pass through the glass (black curve). Red curve shows the difference in the spectral phases of the two laser pulses. The sign of this spectral phase difference is flipped for a direct comparison with the theoretical estimation. The linear part of the spectral phases of the laser pulses has been removed in the analysis. Green curve shows the simulated phase profile assuming a GDD value of 50 fs². Open access funded by Max Planck Society. This article has not yet been cited by other publications.","PeriodicalId":23,"journal":{"name":"ACS Photonics","volume":"49 1","pages":""},"PeriodicalIF":7.0,"publicationDate":"2025-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142992634","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}