ACS Photonics最新文献

{"title":"Insight on Self-Emissive μLED Display from Correlations between Surface Current and Efficiency/Emission Properties of Size-Dependent μLEDs","authors":"Woo Jin Baek, Juhyuk Park, Hyun Soo Kim, Daemyeong Geum, Jung-Hong Min, Tae-Hoon Chung, Sanghyeon Kim","doi":"10.1021/acsphotonics.5c00376","DOIUrl":"https://doi.org/10.1021/acsphotonics.5c00376","url":null,"abstract":"III–V semiconductor-based micro-light-emitting diodes (μLEDs) have emerged as a promising candidate for next-generation displays, particularly in near-eye display (NED) applications. However, several physical constraints, including size-dependent efficiency degradation, color purity, and emission uniformity, pose significant challenges to the commercialization of μLED displays. This study investigates the underlying factors contributing to these limitations, focusing on the surface current behavior of the μLEDs. By examination of the size-dependent electrical and optical properties, as well as the emission behaviors of nitride-based blue, green, and red (RGB), as well as phosphide-based red μLEDs, correlations between surface current behavior and size-dependent efficiency degradation of μLEDs are established. The findings strongly suggest that the inhibition of carrier migration to the sidewall is the key to addressing the size-dependent efficiency degradation. However, our analysis of the emission behaviors reveals that carrier localization-induced size-immunity properties in nitride-based green and red μLEDs may benefit the size-dependent efficiency but not as a display pixel due to the nonuniform emission patterns. These results indicate that the degree of size-dependent efficiency degradation is not the sole criterion for consideration of RGB subpixels. This analysis provides insights into the surface current characteristics of both nitride-based and phosphide-based μLEDs, offering strategies to overcome the identified physical constraints.","PeriodicalId":23,"journal":{"name":"ACS Photonics","volume":"35 1","pages":""},"PeriodicalIF":7.0,"publicationDate":"2025-06-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144305155","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":"Mapping Plasmon-Enhanced Photocurrent in Single Au Nanoplate/MoS2 Heterostructures","authors":"Tiepei Geng, Le Wang, Ningneng Hu, Hao Li, Heng Zhang, Xingjian Feng, Liang Li, Jian-Hua Jiang, Luis M. Liz-Marzán, Weihai Ni","doi":"10.1021/acsphotonics.5c00701","DOIUrl":"https://doi.org/10.1021/acsphotonics.5c00701","url":null,"abstract":"Two-dimensional MoS₂ is a promising material for applications in energy conversion or light harvesting, but the weak light absorption by monolayer MoS₂ hinders its direct application in devices. To enhance the absorption of MoS₂, various strategies have been developed based on metal–semiconductor heterostructures, where multiple processes can be effective, depending on subtle local nanoscale parameters. Revealing key factors in such processes requires characterization on single heterostructures, at the micro- or even nanoscale. We present direct photocurrent mapping (PCM) on single Au nanoplate/MoS₂ heterostructures inside a photoelectrochemical cell, which reveals intense photocurrent signal at the nanoplate edges. The Au nanoplate/MoS₂/TiO₂ heterostructure exhibits a better performance in comparison to MoS₂/Au nanoplate/TiO₂ structure, achieving maximum photocurrent performance of 32.8 nA under 600 nm excitation wavelength, which represents an enhancement factor of 32× due to the heterostructure. Our PCM measurements indicate that maximum performance is achieved at different excitation wavelengths for varying excitation power, with a transition from a linear power dependence at long excitation wavelengths to superlinear dependence at short excitation wavelengths. A thorough theoretical analysis including both E-field and plasmonic thermal effects revealed different enhancement factors at different excitation wavelengths and powers, in agreement with the experiment. We conclude that the performance of the MoS₂ layer is enhanced by plasmon resonance energy transfer in the spectral range with strong plexcitionic resonance coupling, at longer wavelengths, whereas it is promoted by a thermal effect due to Au interband transitions at shorter wavelengths (<600 nm).","PeriodicalId":23,"journal":{"name":"ACS Photonics","volume":"153 1","pages":""},"PeriodicalIF":7.0,"publicationDate":"2025-06-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144305198","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":"Bipedal Anchoring Strategy via Dicarboxylic Acid Molecules for Efficient NiOx-Based Perovskite Solar Cells","authors":"Haoyu Ge, Xianzhao Wang, Xinhang Cai, Yuting Song, Hai Xu, Aijun Li, Xiao-Feng Wang","doi":"10.1021/acsphotonics.5c00386","DOIUrl":"https://doi.org/10.1021/acsphotonics.5c00386","url":null,"abstract":"Though nickel oxide (NiO_<i>x</i>) has been widely used as a hole transport layer in inverted perovskite solar cells (PSCs), the performance of NiO_<i>x</i>-based PSCs is limited by low conduction of NiO_<i>x</i>, surface defects, lattice mismatch, poor energy level alignment, and redox reactions at the NiO_<i>x</i>/perovskite interface. To address these issues, a series of small dicarboxylic acid molecules (DAMs) are introduced as a buffer layer between NiO_<i>x</i> and the perovskite films in this study. Utilizing the double carboxylic acid moieties to orderly anchor NiO_<i>x</i>, DAMs effectively passivate defects of NiO_<i>x</i> and inhibit interfacial redox reactions. Among the DAMs, pyridine-3,5-dicarboxylic acid (P35DA) owns unique pyridine rings, which induce more favorable dipole moments for energy level alignment and interact with uncoordinated lead ion, thus regulating the crystallization of perovskite, reducing the interfacial tensile strain, and suppressing nonradiative recombination. Consequently, the devices based on NiO_<i>x</i>/P35DA exhibit the champion power conversion efficiency (PCE) of 24.05% and 21.48% for 1.56 and 1.68 eV PSCs, respectively. Meanwhile, the unencapsulated devices maintain 81% of their initial PCE after being stored in air with 50–60% relative humidity for 1200 h, exhibiting remarkable environmental stability.","PeriodicalId":23,"journal":{"name":"ACS Photonics","volume":"10 1","pages":""},"PeriodicalIF":7.0,"publicationDate":"2025-06-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144278544","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":"In-Plane Excitation of Wedge Plasmon Polariton Modes in a Double Nanohole for Trapping and Sensing Nanoparticles","authors":"Mostafa Ghorbanzadeh","doi":"10.1021/acsphotonics.5c01008","DOIUrl":"https://doi.org/10.1021/acsphotonics.5c01008","url":null,"abstract":"Double nanohole (DNH) optical tweezers with high gradient forces at the cusps have been extensively used to trap and analyze single nanoparticles (NPs), such as DNA and proteins, and their interactions in real-time, without the need for labels or tethers. To excite plasmonic modes in DNHs fabricated on a flat thin gold film, a large-scale free-space optical setup with a well-aligned laser focus is needed. Fabricating DNHs at the fiber’s end removes the need for a bulky microscope setup, but complicates the fabrication process and loses its integrability to realize lab-on-a-chip devices. Here, an integrated DNH-based plasmonic tweezer is proposed in which the wedge plasmon polariton (WPP) modes at the cusps of a DNH are <i>locally</i> excited by a photonic tapered planar waveguide that is compatible with other integrated devices. Numerical results confirm the excitation of WPP modes under certain conditions and a good sensitivity of the transmitted/reflected power in the presence of trapped NPs to <i>optically</i> sense them. Also, comparing the optical forces calculated by Maxwell stress tensor (MST) and point-dipole approximation reveals that the proposed structure benefits from the self-induced back-action (SIBA) effect to trap NPs with lower light intensity. Moreover, due to the different excitation methods, the proposed structure can provide the opportunity to apply an electric field along the DNH’s cusp axis to analyze trapped NPs <i>electrically</i>, apply an electric field during optical measurements, apply dielectrophoresis forces, and integrate miniaturized parallel DNH tweezers with individual operation on a single chip. Numerical simulations give deterministic guidance and potential applications of the proposed excitation scheme to develop integrated DNH-based optical tweezers.","PeriodicalId":23,"journal":{"name":"ACS Photonics","volume":"12 1","pages":""},"PeriodicalIF":7.0,"publicationDate":"2025-06-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144278549","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":"Where Does Light Come From: Propagation and Emission of Surface Plasmon Polaritons in Plasmonic Crystals Visualized by Cathodoluminescence","authors":"Izzah Machfuudzoh, Sotatsu Yanagimoto, Naoki Yamamoto, Takumi Sannomiya","doi":"10.1021/acsphotonics.5c00233","DOIUrl":"https://doi.org/10.1021/acsphotonics.5c00233","url":null,"abstract":"Ultrafast information processing with low energy consumption is in high demand in optical networks, which leverage light in complex interconnected media, such as nanophotonic device modules. However, the nanoscopic correlation between the excitation and emission spaces of optical light─key to the foundation of nanophotonic devices, encompassing excitation (input), propagation (reservoir), and emission (output)─remains elusive. This study addresses the challenge of nanoscopic observation of optical input and output through a comprehensive investigation of the pathways in a model system based on surface plasmon polaritons in one-dimensional plasmonic crystals (PlCs), using cathodoluminescence imaging. By analyzing the momentum and emission position of optical modes, the interplay between excitation and photon emission in PlCs is clarified. The results reveal the spatial distribution of multiple emission positions across the samples arising from the modulated phases of the emitted light following point excitation of SPPs, with varying distributions and interference conditions observed for different excitation positions.","PeriodicalId":23,"journal":{"name":"ACS Photonics","volume":"609 1","pages":""},"PeriodicalIF":7.0,"publicationDate":"2025-06-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144278545","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-Performance Electron Transport in CsPbBr3 Perovskite Crystals for Room-Temperature Radiation Detection","authors":"Mustafa Unal, Indra R. Pandey, Sujita Karki, Duck Young Chung, Mercouri G. Kanatzidis","doi":"10.1021/acsphotonics.5c00458","DOIUrl":"https://doi.org/10.1021/acsphotonics.5c00458","url":null,"abstract":"All-inorganic CsPbBr₃ perovskite material has gained considerable attention in recent years for its unique properties, including exceptional room-temperature semiconductor behavior for hard radiation detection. This semiconductor has achieved record-breaking energy resolutions in room-temperature gamma-ray detection. Despite the high energy resolutions achieved, performance in CsPbBr₃ detectors has primarily relied on hole collection due to the lower likelihood of hole trapping in halide perovskites, leaving the potential of electron transport largely underexplored. In this study, we explore the electron transport properties of Bridgman-grown CsPbBr₃ crystals with thicknesses below 2 mm. Remarkably, we demonstrate high spectral performance using electron collection, achieving energy resolutions of 2.5% for ¹³⁷Cs (662 keV), 4.2% for ⁵⁷Co (122 keV), and 7.8% for ²⁴¹Am (59.5 keV). These results are comparable to those obtained via hole collection. The mobility–lifetime (μ·τ) product value for electrons reached ∼1.03 × 10^–3 cm²/V. Furthermore, mobilities estimated through pulse rise time analysis yielded similar values of ∼27 cm²/(V s) for both electrons and holes. This work provides the first systematic evidence that electron collection is viable in thin CsPbBr₃ detectors, highlighting their potential for use in high-performance radiation detection by electron collection.","PeriodicalId":23,"journal":{"name":"ACS Photonics","volume":"5 1","pages":""},"PeriodicalIF":7.0,"publicationDate":"2025-06-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144278546","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":"Ultrasensitive Pressure Sensing with Boron Vacancy Defects in Hexagonal Boron Nitride: In-Situ Pressure Imaging of Two-Dimensional Heterostructures under High Pressure","authors":"Cheng Zhong, Di Mai, Yupeng Wang, He Wang, Rucheng Dai, Zhongping Wang, Xiaoyu Sun, Zengming Zhang","doi":"10.1021/acsphotonics.5c00670","DOIUrl":"https://doi.org/10.1021/acsphotonics.5c00670","url":null,"abstract":"<i>In-situ</i> pressure imaging poses significant challenges due to strict experimental conditions. In this work, we integrate two-dimensional (2D) hexagonal boron nitride (<i>h</i>BN) with negative boron vacancy (V_B^–) spin defects directly into the chamber of the diamond anvil cell (DAC), enabling the first systematic investigation of their optical and spin properties under high pressure. Pressure-induced red-shifts of photoluminescence and reduced photon counts of the V_B^– defects are observed. The zero-field splitting parameter <i>D</i> of the V_B^– defects exhibits a linear pressure dependency at 57.4 MHz/GPa, with a pressure sensitivity of 0.32 <i></i><math display=\"inline\"><mi mathvariant=\"normal\">MPa</mi><mo>/</mo><msqrt><mi mathvariant=\"normal\">Hz</mi></msqrt></math>, surpassing that of the nitrogen-vacancy centers in diamond and the silicon-vacancy centers in silicon carbon. Furthermore, by utilizing the V_B^– defects as ultrasensitive pressure quantum sensors, we have successfully mapped the inhomogeneous pressure distribution within an <i>h</i>BN/twisted double trilayer graphene/<i>h</i>BN device under compression via wide-field quantum imaging. The images reveal a pressure gradient increasing with loading. These results provide insight into the spin properties of V_B^– defects and the potential of <i>in-situ</i> pressure and magnetic imaging for 2D heterojunction devices under extreme conditions.","PeriodicalId":23,"journal":{"name":"ACS Photonics","volume":"44 1","pages":""},"PeriodicalIF":7.0,"publicationDate":"2025-06-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144278548","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":"Ultrabroadband Infrared Polarization Beam Combiner Based on Calomel Crystals with High Efficiency Exceeding 92% and Low Wavefront Distortion","authors":"Zhongjie Yue, Lulu Yang, Jian Song, Zhongjun Zhai, Lin Liu, Xin Wang, Xutang Tao, Guodong Zhang","doi":"10.1021/acsphotonics.5c00664","DOIUrl":"https://doi.org/10.1021/acsphotonics.5c00664","url":null,"abstract":"Midwave and long-wave infrared (MW &amp; LWIR) lasers are essential for applications such as infrared detection and counteraction. However, generating high-power MW &amp; LWIR lasers directly is challenging. Polarization beam combining technology provides an effective method to achieve high-power lasers with excellent beam quality. This study introduces Glan–Foucault type polarization beam combiner (PBC) based on the calomel (Hg₂Cl₂) single crystal (SC), which exhibits an exceptionally wide transmission range (0.38–25 μm), ultrahigh birefringence of 0.533@4.6 μm, and a favorable laser-induced damage threshold (LIDT₍₀₀₁₎ = 8.06 J/cm²@3.5 μm). The designed PBCs demonstrate an outstanding extinction ratio (ER) of up to 40 dB and a theoretical maximal transmittance of 81% across the full spectrum. When two fundamental mode Gaussian beams from the quantum cascade lasers (QCLs) were combined, the PBCs with infrared antireflection (AR) coatings achieved combining efficiencies of 93.5% at 4.6 μm and 92.4% at 9.2 μm, along with beam quality factors <i>M</i>² of 1.23 and 1.17, respectively, without noticeable degradation. This work presents a novel polarization component for efficiently scaling the laser output power and maintaining good beam quality across mid- and far-infrared range.","PeriodicalId":23,"journal":{"name":"ACS Photonics","volume":"9 1","pages":""},"PeriodicalIF":7.0,"publicationDate":"2025-06-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144278547","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":"Dark Excitons and Hot Electrons Modulate Exciton-Photon Strong Coupling in Metal–Organic Optical Microcavities","authors":"Pavel V. Kolesnichenko, Manuel Hertzog, Felix Hainer, Oskar Kefer, Jana Zaumseil, Tiago Buckup","doi":"10.1021/acsphotonics.4c01972","DOIUrl":"https://doi.org/10.1021/acsphotonics.4c01972","url":null,"abstract":"Polaritons, formed as a result of strong hybridization of matter with light, are promising for important applications, including organic solar cells, optical logic gates, and qubits. Owing to the large binding energies of Frenkel excitons (matter), strong matter–light coupling phenomena are possible at room temperature, high exciton densities, and even with low-quality factor microcavities. In such cases, because of the high degree of delocalization of polaritons, simultaneous effects from dark excitons and hot electrons may affect the performance of potential devices. Their understanding, therefore, is of high importance, but their disentanglement in optical spectroscopy has thus far remained unattainable. Here, we overcome this challenge by careful and systematic analysis of transient polaritonic spectra, supported by analytical models. In doing so, we conclude that dark excitons affect the strength of exciton–photon coupling and manifest themselves as Fano-like polaritonic gain-loss spectra. Free electrons add an additional loss component and imprint two-temperature dynamics on the polaritonic response. The general methodology developed can be applied to a variety of other microcavity structures. Our findings are significant for distinguishing polaritons and other excitations in studies of polariton–electron and plasmon–electron coupling phenomena, as well as photonic control over photophysical and photochemical processes.","PeriodicalId":23,"journal":{"name":"ACS Photonics","volume":"31 14 1","pages":""},"PeriodicalIF":7.0,"publicationDate":"2025-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144269034","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":"Unveiling Low-Energy Emission in 2D Organic–Inorganic Perovskites: A Photorecycling and Electron–Phonon Coupling Study","authors":"Maykon A. Lemes, Cássio C. Soares, Eliane A. Morais, Yina J. Onofre, Marcio P. F. de Godoy, Carlos W. A. Paschoal, Jose J. S. Acuña, Carlos Mera Acosta, Jose Antonio Souza","doi":"10.1021/acsphotonics.5c00837","DOIUrl":"https://doi.org/10.1021/acsphotonics.5c00837","url":null,"abstract":"2D hybrid organic–inorganic perovskites have demonstrated outstanding optoelectronic properties. Among their photophysical features, low-energy photoluminescence (PL) peaks are often observed, yet their origin remains not fully understood, particularly due to the coexistence of multiple possible emission pathways. To address this, we hypothesized that structural rigidity─determined by the organic spacer─may influence photon recycling and, consequently, the nature of low-energy emission. We thus investigated the origin of low-energy emission in both (BA)₂PbBr₄ and (PEA)₂PbBr₄ across different material morphologies including microcrystals and colloidal nanoplatelets. Through a combination of structural characterization, steady-state and temperature-dependent PL measurements, and density functional theory (DFT) calculations, we demonstrate that the low-energy emission observed in microcrystalline samples arises predominantly from photon recycling rather than self-trapped excitons (STEs) or defect states. Importantly, we find that the size and orientation of the crystals strongly affect the observed PL, supporting the interpretation that total internal reflection (TIR) within the perovskite acts as a waveguiding mechanism for photon propagation and reabsorption. Our findings reveal that the structural rigidity of the perovskite plays a crucial role in governing photorecycling photon propagation. Specifically, the flexible lattice of (BA)₂PbBr₄ facilitates photon recycling with energy losses, resulting in pronounced low-energy emission, whereas the rigid structure of (PEA)₂PbBr₄ better preserves the photon energy during propagation. The observed differences in electron–phonon coupling further support the role of structural flexibility in modulating the transport of emitted photons. These insights provide a deeper understanding of light-matter interactions in 2D perovskites and highlight the importance of crystal engineering in optimizing their optical properties. By tailoring the organic spacer and controlling structural rigidity, it is possible to fine-tune emission characteristics for applications in optoelectronic devices.","PeriodicalId":23,"journal":{"name":"ACS Photonics","volume":"41 1","pages":""},"PeriodicalIF":7.0,"publicationDate":"2025-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144268949","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}