Recent advancements in the study of light-matter interactions between optical cavities and two-dimensional materials have underscored the significance of strong coupling phenomena, facilitating innovative developments in optical devices and quantum information processing. In this study, we explored the interaction between Bloch-surface plasmon polaritons from a square Ag nanohole array and A exciton of monolayer WS2, demonstrating a significant Rabi splitting of 74 meV via angle-resolved transient absorption spectroscopy. By analyzing the damping process of the upper and lower branches, we observe that the lower branch decays significantly faster than the upper branch. These findings not only enhance our understanding of exciton-polariton but also point to potential applications in Bose–Einstein condensation, nanophotonics, and quantum information.
{"title":"Ultrafast Investigation of the Strong Coupling System between Square Ag Nanohole Array and Monolayer WS2","authors":"Jinyu Yang, Leyi Zhao, Zixuan Song, Jiamin Xiao, Lingyao Li, Guangjun Zhang, Wenxin Wang","doi":"10.1021/acs.nanolett.4c05053","DOIUrl":"https://doi.org/10.1021/acs.nanolett.4c05053","url":null,"abstract":"Recent advancements in the study of light-matter interactions between optical cavities and two-dimensional materials have underscored the significance of strong coupling phenomena, facilitating innovative developments in optical devices and quantum information processing. In this study, we explored the interaction between Bloch-surface plasmon polaritons from a square Ag nanohole array and A exciton of monolayer WS<sub>2</sub>, demonstrating a significant Rabi splitting of 74 meV via angle-resolved transient absorption spectroscopy. By analyzing the damping process of the upper and lower branches, we observe that the lower branch decays significantly faster than the upper branch. These findings not only enhance our understanding of exciton-polariton but also point to potential applications in Bose–Einstein condensation, nanophotonics, and quantum information.","PeriodicalId":53,"journal":{"name":"Nano Letters","volume":"15 1","pages":""},"PeriodicalIF":10.8,"publicationDate":"2025-02-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143435754","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-02-18DOI: 10.1021/acs.nanolett.4c06473
Camino Martín-Sánchez, Ana Sánchez-Iglesias, José Antonio Barreda-Argüeso, Jean-Paul Itié, Paul Chauvigne, Luis M. Liz-Marzán, Fernando Rodríguez
We report on the crystallographic structure of penta-twinned gold nanoparticles. Although gold typically exhibits a face-centered cubic (fcc) lattice, other phases have been reported in some nanoscale systems. We show that the crystallographic system and the lattice parameters of the gold unit cell strongly depend on the nanoparticle geometry, for a wide size range. Specifically, we show that decahedra exhibit a body-centered tetragonal structure (I4/mmm), whereas rods and bipyramids exhibit a body-centered orthorhombic structure (Immm). These changes in the crystallographic structure are explained by the elastic lattice distortions required to close the mismatch gap in penta-twinned nanoparticles, with respect to fcc single-crystal gold nanoparticles. The effects of nanoparticle shape and size on the surface pressure and the subsequent distortions are additionally discussed.
{"title":"Origin of the Rich Polymorphism of Gold in Penta-Twinned Nanoparticles","authors":"Camino Martín-Sánchez, Ana Sánchez-Iglesias, José Antonio Barreda-Argüeso, Jean-Paul Itié, Paul Chauvigne, Luis M. Liz-Marzán, Fernando Rodríguez","doi":"10.1021/acs.nanolett.4c06473","DOIUrl":"https://doi.org/10.1021/acs.nanolett.4c06473","url":null,"abstract":"We report on the crystallographic structure of penta-twinned gold nanoparticles. Although gold typically exhibits a face-centered cubic (<i>fcc</i>) lattice, other phases have been reported in some nanoscale systems. We show that the crystallographic system and the lattice parameters of the gold unit cell strongly depend on the nanoparticle geometry, for a wide size range. Specifically, we show that decahedra exhibit a body-centered tetragonal structure (<i>I</i>4/<i>mmm</i>), whereas rods and bipyramids exhibit a body-centered orthorhombic structure (<i>Immm</i>). These changes in the crystallographic structure are explained by the elastic lattice distortions required to close the mismatch gap in penta-twinned nanoparticles, with respect to <i>fcc</i> single-crystal gold nanoparticles. The effects of nanoparticle shape and size on the surface pressure and the subsequent distortions are additionally discussed.","PeriodicalId":53,"journal":{"name":"Nano Letters","volume":"85 1","pages":""},"PeriodicalIF":10.8,"publicationDate":"2025-02-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143435757","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-02-18DOI: 10.1021/acs.nanolett.4c06543
Julian Picker, Mahdi Ghorbani-Asl, Maximilian Schaal, Silvan Kretschmer, Felix Otto, Marco Gruenewald, Christof Neumann, Torsten Fritz, Arkady V. Krasheninnikov, Andrey Turchanin
Janus SeMoS monolayers (MLs) are synthetic 2D materials with unique electronic properties, as theory predicts, but their experimental exploration has been hindered by the low quality of the samples. Here we report a synthesis of high-quality Janus MLs on gold substrates by thermal exchange reaction taking place at the ML/Au(111) interface. The synthesized Janus SeMoS MLs were characterized by complementary techniques, and insights into the topography and electronic properties of the system were obtained. Specifically, due to the lattice mismatch with the Au(111), a moiré pattern with a periodicity of 2.9 nm was observed. A precise experimental determination of the lattice constant of Janus SeMoS of 3.22 ± 0.01 Å was obtained, and the measured spin–orbit splitting at the K point of the valence band was found to be 170 ± 15 meV, matching well the results of the density functional theory calculations.
{"title":"Atomic Structure and Electronic Properties of Janus SeMoS Monolayers on Au(111)","authors":"Julian Picker, Mahdi Ghorbani-Asl, Maximilian Schaal, Silvan Kretschmer, Felix Otto, Marco Gruenewald, Christof Neumann, Torsten Fritz, Arkady V. Krasheninnikov, Andrey Turchanin","doi":"10.1021/acs.nanolett.4c06543","DOIUrl":"https://doi.org/10.1021/acs.nanolett.4c06543","url":null,"abstract":"Janus SeMoS monolayers (MLs) are synthetic 2D materials with unique electronic properties, as theory predicts, but their experimental exploration has been hindered by the low quality of the samples. Here we report a synthesis of high-quality Janus MLs on gold substrates by thermal exchange reaction taking place at the ML/Au(111) interface. The synthesized Janus SeMoS MLs were characterized by complementary techniques, and insights into the topography and electronic properties of the system were obtained. Specifically, due to the lattice mismatch with the Au(111), a moiré pattern with a periodicity of 2.9 nm was observed. A precise experimental determination of the lattice constant of Janus SeMoS of 3.22 ± 0.01 Å was obtained, and the measured spin–orbit splitting at the <i>K</i> point of the valence band was found to be 170 ± 15 meV, matching well the results of the density functional theory calculations.","PeriodicalId":53,"journal":{"name":"Nano Letters","volume":"29 1","pages":""},"PeriodicalIF":10.8,"publicationDate":"2025-02-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143435758","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-02-18DOI: 10.1021/acs.nanolett.4c06395
Jincheng Hou, Shaojie Hu, Long You
Spin waves exhibit high-speed, low-energy information transmission and encoding capabilities. The core component, the spin wave generator, currently faces challenges of high energy consumption and integration difficulties. This study proposes a spin wave generator based on a ferroelectric/ferromagnetic heterostructure. This generator utilizes an electric field to control the Dzyaloshinskii–Moriya interaction (DMI), regulating the dynamics of magnetic topological states like skyrmions, thereby achieving low-power excitation of spin waves. First, we conducted a theoretical analysis to study the impact of oscillatory voltage-controlled DMI on the dynamic properties of skyrmions, identifying the excitation conditions for both the breathing mode and the spin wave mode. Additionally, we clarified the relationship among spin wave intensity, DMI coefficient, and frequency. Finally, we validated the theoretical predictions of the spin wave excitation in this structure through micromagnetic simulations. This work points the way toward developing ultrahigh frequency, low-power, and highly stable spin wave generators.
{"title":"Excitation of Spin Waves by Oscillatory Voltage-Controlled Dzyaloshinskii–Moriya Interaction in Ferroelectric/Skyrmion Heterostructure","authors":"Jincheng Hou, Shaojie Hu, Long You","doi":"10.1021/acs.nanolett.4c06395","DOIUrl":"https://doi.org/10.1021/acs.nanolett.4c06395","url":null,"abstract":"Spin waves exhibit high-speed, low-energy information transmission and encoding capabilities. The core component, the spin wave generator, currently faces challenges of high energy consumption and integration difficulties. This study proposes a spin wave generator based on a ferroelectric/ferromagnetic heterostructure. This generator utilizes an electric field to control the Dzyaloshinskii–Moriya interaction (DMI), regulating the dynamics of magnetic topological states like skyrmions, thereby achieving low-power excitation of spin waves. First, we conducted a theoretical analysis to study the impact of oscillatory voltage-controlled DMI on the dynamic properties of skyrmions, identifying the excitation conditions for both the breathing mode and the spin wave mode. Additionally, we clarified the relationship among spin wave intensity, DMI coefficient, and frequency. Finally, we validated the theoretical predictions of the spin wave excitation in this structure through micromagnetic simulations. This work points the way toward developing ultrahigh frequency, low-power, and highly stable spin wave generators.","PeriodicalId":53,"journal":{"name":"Nano Letters","volume":"1 1","pages":""},"PeriodicalIF":10.8,"publicationDate":"2025-02-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143435756","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Doping has been extensively studied as an effective means of modulating the electrical properties of two-dimensional (2D) semiconductors. However, precise methods for p- and n-type doping in specific regions remain underdeveloped, hindering high-performance devices and integrated circuits. We present a novel technique, template-assisted dry transfer doping (TADTD), which enables precise control over doping regions, patterns, polarities, and levels in 2D semiconductors. Utilizing photolithography, TADTD allows for the creation of patterned dopant films that are transferred to MoTe2 without the damaging effects of traditional methods. The effectiveness of TADTD is demonstrated through the fabrication of p- and n-type MoTe2 field-effect transistors (FETs) using molecular dopants Magic Blue and N-DMBI, respectively. Additionally, we construct functional complementary logic circuits, including inverters and NAND and NOR gates, utilizing selectively doped MoTe2 channels. The precise doping control achieved with TADTD highlights its potential for advancing 2D semiconductor technology and integration into future CMOS applications.
{"title":"Template-Assisted Dry Transfer Doping of Two-Dimensional Semiconductors","authors":"Yu Zhang, Ping-An Chen, Zheyi Lu, Yu Liu, Huan Wei, Jiangnan Xia, Jiaqi Ding, Zhenqi Gong, Chengyuan Peng, Wenpei Shi, Yuan Liu, Lei Liao, Yuanyuan Hu","doi":"10.1021/acs.nanolett.4c06220","DOIUrl":"https://doi.org/10.1021/acs.nanolett.4c06220","url":null,"abstract":"Doping has been extensively studied as an effective means of modulating the electrical properties of two-dimensional (2D) semiconductors. However, precise methods for p- and n-type doping in specific regions remain underdeveloped, hindering high-performance devices and integrated circuits. We present a novel technique, template-assisted dry transfer doping (TADTD), which enables precise control over doping regions, patterns, polarities, and levels in 2D semiconductors. Utilizing photolithography, TADTD allows for the creation of patterned dopant films that are transferred to MoTe<sub>2</sub> without the damaging effects of traditional methods. The effectiveness of TADTD is demonstrated through the fabrication of p- and n-type MoTe<sub>2</sub> field-effect transistors (FETs) using molecular dopants Magic Blue and N-DMBI, respectively. Additionally, we construct functional complementary logic circuits, including inverters and NAND and NOR gates, utilizing selectively doped MoTe<sub>2</sub> channels. The precise doping control achieved with TADTD highlights its potential for advancing 2D semiconductor technology and integration into future CMOS applications.","PeriodicalId":53,"journal":{"name":"Nano Letters","volume":"3 1","pages":""},"PeriodicalIF":10.8,"publicationDate":"2025-02-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143427275","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Magnetic skyrmion bags with diverse topological charges, Q, offer prospects for future spintronic devices based on freedom of Q, while their emergence in van der Waals magnets holds the potential in developing Q-based 2D topological spintronics. However, previous room temperature skyrmion bags necessitate special anisotropy engineering through disorder Fe intercalation, and the stable phase diagram for skyrmion bags across room temperature regions is lacking. Here, we demonstrate the observation and electrical manipulation of room temperature skyrmion bags in Fe3–xGaTe2 without specially designed Fe intercalation. Combining the pulsed currents with the assistance of magnetic fields, skyrmion bags with various topological charges are generated and annihilated. Especially double nested skyrmion bags are also discovered at room temperature. The stable temperature–field diagram of skyrmion bags has been established. We also demonstrate electrically controlled topological phase transformations of skyrmion bags. Our results will provide novel insights for the design of 2D skyrmion-based high-performance devices.
{"title":"Stable Néel-Twisted Skyrmion Bags in a van der Waals Magnet Fe3–xGaTe2 at Room Temperature","authors":"Jialiang Jiang, Yaodong Wu, Lingyao Kong, Yongsen Zhang, Sheng Qiu, Huanhuan Zhang, Yajiao Ke, Shouguo Wang, Mingliang Tian, Jin Tang","doi":"10.1021/acs.nanolett.4c06281","DOIUrl":"https://doi.org/10.1021/acs.nanolett.4c06281","url":null,"abstract":"Magnetic skyrmion bags with diverse topological charges, <i>Q</i>, offer prospects for future spintronic devices based on freedom of <i>Q</i>, while their emergence in van der Waals magnets holds the potential in developing <i>Q</i>-based 2D topological spintronics. However, previous room temperature skyrmion bags necessitate special anisotropy engineering through disorder Fe intercalation, and the stable phase diagram for skyrmion bags across room temperature regions is lacking. Here, we demonstrate the observation and electrical manipulation of room temperature skyrmion bags in Fe<sub>3–<i>x</i></sub>GaTe<sub>2</sub> without specially designed Fe intercalation. Combining the pulsed currents with the assistance of magnetic fields, skyrmion bags with various topological charges are generated and annihilated. Especially double nested skyrmion bags are also discovered at room temperature. The stable temperature–field diagram of skyrmion bags has been established. We also demonstrate electrically controlled topological phase transformations of skyrmion bags. Our results will provide novel insights for the design of 2D skyrmion-based high-performance devices.","PeriodicalId":53,"journal":{"name":"Nano Letters","volume":"3 1","pages":""},"PeriodicalIF":10.8,"publicationDate":"2025-02-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143427276","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-02-17DOI: 10.1021/acs.nanolett.4c06501
Seth D. Waugaman, Mykyta Dementyev, Elmira Abbasi GharehTapeh, Carlos G. Lopez, Robert T. Mathers, Robert J. Hickey
Tailoring polymer gel functionality by loading small molecules and nanoparticles is critical for drug delivery and tissue regeneration. Typically, solute loading in gels correlates with the degree of solvent swelling, which is controlled by the cross-link density and polymer/solvent interactions. However, the general assumption that the degree of swelling is the primary factor for nanoparticle loading is incorrect. Here, we demonstrate that the pairwise interactions between the polymer, solvent, and solute dictate the solute loading in gels. We performed gel loading studies of ligand-stabilized gold nanoparticles using different solvents, polymer network hydrophobicity, and cross-link densities, and found that nanoparticle distribution between polymer and solvent correlate with calculated thermodynamic partition coefficients. Despite previous assumptions that the maximum nanoparticle loading occurs at the highest degree of gel swelling, we reveal that nanoparticles preferentially load into gels with lower solvent swelling if ligand/polymer interactions are more favorable than ligand/solvent interactions.
{"title":"Nanoparticle Loading in Swollen Polymer Gels: An Unexpected Thermodynamic Twist","authors":"Seth D. Waugaman, Mykyta Dementyev, Elmira Abbasi GharehTapeh, Carlos G. Lopez, Robert T. Mathers, Robert J. Hickey","doi":"10.1021/acs.nanolett.4c06501","DOIUrl":"https://doi.org/10.1021/acs.nanolett.4c06501","url":null,"abstract":"Tailoring polymer gel functionality by loading small molecules and nanoparticles is critical for drug delivery and tissue regeneration. Typically, solute loading in gels correlates with the degree of solvent swelling, which is controlled by the cross-link density and polymer/solvent interactions. However, the general assumption that the degree of swelling is the primary factor for nanoparticle loading is incorrect. Here, we demonstrate that the pairwise interactions between the polymer, solvent, and solute dictate the solute loading in gels. We performed gel loading studies of ligand-stabilized gold nanoparticles using different solvents, polymer network hydrophobicity, and cross-link densities, and found that nanoparticle distribution between polymer and solvent correlate with calculated thermodynamic partition coefficients. Despite previous assumptions that the maximum nanoparticle loading occurs at the highest degree of gel swelling, we reveal that nanoparticles preferentially load into gels with lower solvent swelling if ligand/polymer interactions are more favorable than ligand/solvent interactions.","PeriodicalId":53,"journal":{"name":"Nano Letters","volume":"10 1","pages":""},"PeriodicalIF":10.8,"publicationDate":"2025-02-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143427282","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-02-17DOI: 10.1021/acs.nanolett.5c00058
Yuriy G. Bushuev
Hierarchical nanoporous particles combine properties of microporous and mesoporous materials that are widely exploited for energy storage and conversion, separation of gases and liquids, water purification and desalination, fabrication of nanodevices, etc. Hierarchical meso/microporous level-2 and level-3 Menger sponge particles immersed in water were investigated using computer simulation methods to demonstrate a synergetic effect of additional porosity on the wettability of materials. The Menger sponge is an object with a fractal dimension. At each level, the particles are composed of the same structural blocks. The hydrophobicity of the blocks was shown to depend on their size and position in the nanoparticles. The additional porosity decreases the hydrophobicity of the particles due to the partial breaking of hydrogen bonds between water molecules in the pores. This effect can be used to tune and modify the hydrophobicity and wettability of bulky porous materials, nanoparticles, and nanostructured surfaces.
{"title":"Effects of Size and Porosity on the Hydrophobicity of Hierarchical Nanoparticles","authors":"Yuriy G. Bushuev","doi":"10.1021/acs.nanolett.5c00058","DOIUrl":"https://doi.org/10.1021/acs.nanolett.5c00058","url":null,"abstract":"Hierarchical nanoporous particles combine properties of microporous and mesoporous materials that are widely exploited for energy storage and conversion, separation of gases and liquids, water purification and desalination, fabrication of nanodevices, etc. Hierarchical meso/microporous level-2 and level-3 Menger sponge particles immersed in water were investigated using computer simulation methods to demonstrate a synergetic effect of additional porosity on the wettability of materials. The Menger sponge is an object with a fractal dimension. At each level, the particles are composed of the same structural blocks. The hydrophobicity of the blocks was shown to depend on their size and position in the nanoparticles. The additional porosity decreases the hydrophobicity of the particles due to the partial breaking of hydrogen bonds between water molecules in the pores. This effect can be used to tune and modify the hydrophobicity and wettability of bulky porous materials, nanoparticles, and nanostructured surfaces.","PeriodicalId":53,"journal":{"name":"Nano Letters","volume":"24 1","pages":""},"PeriodicalIF":10.8,"publicationDate":"2025-02-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143435778","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-02-17DOI: 10.1021/acs.nanolett.4c05809
Pu Guo, Junyao Zhang, Zhekun Hua, Tongrui Sun, Li Li, Shilei Dai, Lize Xiong, Jia Huang
Visual acuity is the ability of the biological retina to distinguish images. High-sensitivity image acquisition improves the quality of visual perception, making images more recognizable for the visual system. Therefore, developing synaptic phototransistors with enhanced photosensitivity is crucial for high-performance artificial vision. Here, organic synaptic phototransistors (OSPs) based on p–n type semiconductor heterojunctions are presented, which demonstrate improved photoresponses and light storage characteristics. As many as 800 potentiation–depression states can be obtained, and the nonlinearity extracted from the long-term potentiation curve is only 0.08. Furthermore, by utilizing light-adjustable synapse-like behaviors, the phototransistors realize a noise reduction function and logic gate transformation. Benefiting from the enhanced photosensitivity of the OSPs, an artificial neural network constructed based on the OSPs shows the recognition accuracy of ∼93% for both handwritten numbers and electrocardiography signals. This research provides an effective path for developing OSPs with enhanced photoelectric performance to advance artificial visual systems.
{"title":"Organic Synaptic Transistors Based on a Semiconductor Heterojunction for Artificial Visual and Neuromorphic Functions","authors":"Pu Guo, Junyao Zhang, Zhekun Hua, Tongrui Sun, Li Li, Shilei Dai, Lize Xiong, Jia Huang","doi":"10.1021/acs.nanolett.4c05809","DOIUrl":"https://doi.org/10.1021/acs.nanolett.4c05809","url":null,"abstract":"Visual acuity is the ability of the biological retina to distinguish images. High-sensitivity image acquisition improves the quality of visual perception, making images more recognizable for the visual system. Therefore, developing synaptic phototransistors with enhanced photosensitivity is crucial for high-performance artificial vision. Here, organic synaptic phototransistors (OSPs) based on p–n type semiconductor heterojunctions are presented, which demonstrate improved photoresponses and light storage characteristics. As many as 800 potentiation–depression states can be obtained, and the nonlinearity extracted from the long-term potentiation curve is only 0.08. Furthermore, by utilizing light-adjustable synapse-like behaviors, the phototransistors realize a noise reduction function and logic gate transformation. Benefiting from the enhanced photosensitivity of the OSPs, an artificial neural network constructed based on the OSPs shows the recognition accuracy of ∼93% for both handwritten numbers and electrocardiography signals. This research provides an effective path for developing OSPs with enhanced photoelectric performance to advance artificial visual systems.","PeriodicalId":53,"journal":{"name":"Nano Letters","volume":"34 1","pages":""},"PeriodicalIF":10.8,"publicationDate":"2025-02-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143427364","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-02-17DOI: 10.1021/acs.nanolett.4c06400
Luigi Camerano, Adolfo O. Fumega, Gianni Profeta, Jose L. Lado
Van der Waals monolayers featuring magnetic states provide fundamental building blocks for artificial quantum matter. Here, we establish the emergence of a multicomponent ground state featuring magneto-orbital excitations of the 3d2-transition metal trihalide VCl3 monolayer. We show that monolayer VCl3 realizes a ground state with simultaneous magnetic and orbital ordering by using density functional theory. Using first-principles methods we derive an effective Hamiltonian with intertwined spin and orbital degrees of freedom, which we demonstrate can be tuned by strain. We show that magneto-orbitons appear as the collective modes of this complex order and arise from coupled orbiton magnon excitations due to the magneto-orbital coupling in the system. Our results establish VCl3 is a promising 2D material to observe emergent magneto-orbital excitations and provides a platform for multicomponent symmetry breaking.
{"title":"Multicomponent Magneto-Orbital Order and Magneto-Orbitons in Monolayer VCl3","authors":"Luigi Camerano, Adolfo O. Fumega, Gianni Profeta, Jose L. Lado","doi":"10.1021/acs.nanolett.4c06400","DOIUrl":"https://doi.org/10.1021/acs.nanolett.4c06400","url":null,"abstract":"Van der Waals monolayers featuring magnetic states provide fundamental building blocks for artificial quantum matter. Here, we establish the emergence of a multicomponent ground state featuring magneto-orbital excitations of the 3<i>d</i><sup>2</sup>-transition metal trihalide VCl<sub>3</sub> monolayer. We show that monolayer VCl<sub>3</sub> realizes a ground state with simultaneous magnetic and orbital ordering by using density functional theory. Using first-principles methods we derive an effective Hamiltonian with intertwined spin and orbital degrees of freedom, which we demonstrate can be tuned by strain. We show that magneto-orbitons appear as the collective modes of this complex order and arise from coupled orbiton magnon excitations due to the magneto-orbital coupling in the system. Our results establish VCl<sub>3</sub> is a promising 2D material to observe emergent magneto-orbital excitations and provides a platform for multicomponent symmetry breaking.","PeriodicalId":53,"journal":{"name":"Nano Letters","volume":"88 1","pages":""},"PeriodicalIF":10.8,"publicationDate":"2025-02-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143427277","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}