Applied Physics Letters最新文献

Micro-tip manipulated origami for robust twisted few-layer graphene

IF 4 2区物理与天体物理

Applied Physics Letters Pub Date : 2025-04-25 DOI: 10.1063/5.0265918

Ruo-Jue Zou, Long Deng, Si-Min Xue, Feng-Fei Cai, Ling-Hui Tong, Yang Zhang, Yuan Tian, Li Zhang, Lijie Zhang, Zhihui Qin, Long-Jing Yin

{"title":"Micro-tip manipulated origami for robust twisted few-layer graphene","authors":"Ruo-Jue Zou, Long Deng, Si-Min Xue, Feng-Fei Cai, Ling-Hui Tong, Yang Zhang, Yuan Tian, Li Zhang, Lijie Zhang, Zhihui Qin, Long-Jing Yin","doi":"10.1063/5.0265918","DOIUrl":"https://doi.org/10.1063/5.0265918","url":null,"abstract":"Twisted few-layer graphene (tFLG) has emerged as an ideal model system for investigating novel strongly correlated and topological phenomena. However, the experimental construction of tFLG with high structural stability is still challenging. Here, we introduce a highly accessible method for fabricating robust tFLG by polymer micro-tip manipulated origami. Through using a self-prepared polymer micro-tip—which is composed of multiple dimethylpolysiloxane, poly(vinyl chloride), and graphite sheets—to fold graphene layers, we fabricated tFLG with different twist angles (0°–30°) and various layers, including twisted bilayers (1 + 1), twisted double-bilayers (2 + 2), twisted double-trilayers (3 + 3), and thicker layers. Even ABC-stacked tFLG were created, such as twisted ABC/ABC and ABC/ABA graphene coexisting in an ABC-ABA domain wall region. We found that the origami-fabricated tFLG exhibits high stability against thermal and mechanical perturbations including heating and transferring, which could be attributed to its special folding and tearing structures. Moreover, based on the rich types of samples, we revealed twist-angle- and stacking-order-dependent Raman characteristics of tFLG, which are valuable for understanding stacking-modulated phonon spectroscopy. Our experiments provide a simple and efficient approach to construct structurally robust tFLG, paving the way for the study of highly stable twisted van der Waals heterostructures.","PeriodicalId":8094,"journal":{"name":"Applied Physics Letters","volume":"44 1","pages":""},"PeriodicalIF":4.0,"publicationDate":"2025-04-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143876367","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Alloying-enhanced ferromagnetic coupling in two-dimensional transition metal carbide MC (M = Cr, Mn) monolayers

IF 4 2区物理与天体物理

Applied Physics Letters Pub Date : 2025-04-25 DOI: 10.1063/5.0253577

Ruoyan Xu, Junlin Luo, Haiyu Meng, Xingxing Jiang, Yee Sin Ang, Xiong-Xiong Xue

{"title":"Alloying-enhanced ferromagnetic coupling in two-dimensional transition metal carbide MC (M = Cr, Mn) monolayers","authors":"Ruoyan Xu, Junlin Luo, Haiyu Meng, Xingxing Jiang, Yee Sin Ang, Xiong-Xiong Xue","doi":"10.1063/5.0253577","DOIUrl":"https://doi.org/10.1063/5.0253577","url":null,"abstract":"Two-dimensional (2D) intrinsic ferromagnetic materials with high ferromagnetic transition temperature (Tc) are critical to the advancement of spintronic device technology. In this study, we present two stable room-temperature ferromagnetic carbides, namely, MC (M = Cr, Mn) monolayers, with Tc values of 384 and 391 K, respectively, along with strong perpendicular magnetic anisotropy (PMA). Furthermore, CrxMn8−xC8 (x=1–7) alloy monolayers are constructed. We demonstrate that the appropriate incorporation of Cr–Mn atomic pairs substantially enhances the ferromagnetic coupling, which is intimately associated with the interactions between metal atoms and their spatial arrangements within the lattice. In particular, the CrMnC2 alloy monolayer exhibits a Tc of 627 K, markedly exceeding that of the parent monolayer. This elevated Tc is attributed to the combined effect of the crystal-field energy difference introduced by the alloying process and the internal stresses arising from the lattice distortion induced by alloying, which jointly enhance ferromagnetic interactions. In addition, CrMnC2 exhibits robust PMA, in-plane magnetic anisotropy induced by structural asymmetry, and slight ferroelastic behavior. These findings offer insights on the impact of alloy engineering on 2D ferromagnetism and highlight a pathway toward high-Tc 2D ferromagnetic materials for practical room-temperature device applications.","PeriodicalId":8094,"journal":{"name":"Applied Physics Letters","volume":"416 1","pages":""},"PeriodicalIF":4.0,"publicationDate":"2025-04-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143876183","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Ultrafast dynamic mid-infrared beam steering via hot-electron modulation in graphene metasurfaces

IF 4 2区物理与天体物理

Applied Physics Letters Pub Date : 2025-04-24 DOI: 10.1063/5.0249898

Qinghua Qin, Leijun Xu, Yiming Yu, Ziying Li, Shuguang Zhu, Zexing Zheng, Huishan Ma, Yu Qian, Jiale He, Weiwei Tang, Guanhai Li, Xiaoshuang Chen

{"title":"Ultrafast dynamic mid-infrared beam steering via hot-electron modulation in graphene metasurfaces","authors":"Qinghua Qin, Leijun Xu, Yiming Yu, Ziying Li, Shuguang Zhu, Zexing Zheng, Huishan Ma, Yu Qian, Jiale He, Weiwei Tang, Guanhai Li, Xiaoshuang Chen","doi":"10.1063/5.0249898","DOIUrl":"https://doi.org/10.1063/5.0249898","url":null,"abstract":"Ultrafast dynamic wavefront control is pivotal for advancing photonics applications in LiDAR, high-resolution imaging, and quantum information processing. Conventional wavefront control techniques, such as mechanical beam steering and liquid-crystal-based modulators, are limited by slow response times and bulky configurations, making them unsuitable for high-speed, on-chip applications. In this work, we propose a graphene-based phase-gradient metasurface that leverages hot-electron dynamics for tunable, ultrafast wavefront control in the mid-infrared regime. By precisely modulating the electron temperature in graphene with femtosecond laser pulses, our device achieves real-time beam steering with a maximum reflection angle shift of 21° within 104 fs, as well as dual-focal length switching. The device demonstrates high reflectivity, continuous 2π phase modulation, and an achromatic response over a substantial bandwidth, making it a robust solution for high-speed optical encoding and adaptive optics. This graphene-based platform provides a compact, reconfigurable solution that overcomes the limitations of traditional and emerging approaches, establishing a foundation for next-generation integrated photonics systems.","PeriodicalId":8094,"journal":{"name":"Applied Physics Letters","volume":"6 1","pages":""},"PeriodicalIF":4.0,"publicationDate":"2025-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143872393","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Very high Curie temperature (470–530 K) in (Ga,Fe)Sb ferromagnetic semiconductor grown by step-flow mode on vicinal GaAs substrates

IF 4 2区物理与天体物理

Applied Physics Letters Pub Date : 2025-04-24 DOI: 10.1063/5.0227990

Pham Nam Hai, Ken Takabayashi, Kota Ejiri, Masaaki Tanaka

引用次数: 0

Transparent and flexible electromagnetic interference shielding thin film based on sulfurized copper iodide

IF 4 2区物理与天体物理

Applied Physics Letters Pub Date : 2025-04-24 DOI: 10.1063/5.0267198

Xiaowan Kang, Xiaojian Chen, Jialin Yang, Junliang Zhao, Chang Yang

引用次数: 0

Nonlinear SU(1,1) interferometers with an on-chip parametric amplifier

IF 4 2区物理与天体物理

Applied Physics Letters Pub Date : 2025-04-23 DOI: 10.1063/5.0261065

Yue Li, Xiaotian Zhu, Jianmin Wang, E. Y. B. Pun, S. T. Chu, Brent E. Little, Z. Y. Ou

引用次数: 0

Polarization-controlled contact barriers enable giant tunneling electroresistance in van der Waals ferroelectric tunnel junctions

IF 4 2区物理与天体物理

Applied Physics Letters Pub Date : 2025-04-23 DOI: 10.1063/5.0258003

Xueyan Bai, Daifeng Zou, Chihou Lei, Zhijian He, Yunya Liu

{"title":"Polarization-controlled contact barriers enable giant tunneling electroresistance in van der Waals ferroelectric tunnel junctions","authors":"Xueyan Bai, Daifeng Zou, Chihou Lei, Zhijian He, Yunya Liu","doi":"10.1063/5.0258003","DOIUrl":"https://doi.org/10.1063/5.0258003","url":null,"abstract":"The regulation of tunneling electroresistance (TER) in two-dimensional (2D) ferroelectric tunnel junctions (FTJs) is crucial for their practical applications. In this Letter, we introduce an innovative approach to manipulate TER by altering the interfacial contact barrier through polarization-induced modifications in interface transport properties. A comprehensive analysis of the electronic structures within heterostructures, consisting of a metallic TaSe2 monolayer and a ferroelectric Sc2CO2 layer, uncovers a dual modulation effect of ferroelectricity on both the Schottky barrier height and the interfacial tunneling barrier. This phenomenon substantiates the influence of polarization on charge carrier transport across the interface. Through calculations employing the non-equilibrium Green's function method, we reveal a significant TER ratio (2.41×1013%) in TaSe2/Sc2CO2-based FTJs. Our findings illustrate that distinct tunneling resistance states can be achieved through polarization reversal, as predicted by the proposed mechanism. These insights enhance the understanding of polarization-mediated TER in 2D FTJs and provide a foundation for the design of next-generation electronic devices leveraging 2D ferroelectric materials.","PeriodicalId":8094,"journal":{"name":"Applied Physics Letters","volume":"27 1","pages":""},"PeriodicalIF":4.0,"publicationDate":"2025-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143872392","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Characterizing the thermo-optic coefficient of gallium phosphide-on-insulator platform using high-quality ring resonators 利用高质量环形谐振器鉴定绝缘体上磷化镓平台的热光学系数

IF 4 2区物理与天体物理

Applied Physics Letters Pub Date : 2025-04-23 DOI: 10.1063/5.0258133

Weiren Cheng, Ning Ding, Xucheng Zhang, Zhenyu Liu, Xingyu Tang, Wenfu Lin, Yifan Wang, Ziyu Pan, Naiqin Bu, Mingjian You, Xingchen Ji, Yi Li, Qiancheng Zhao

{"title":"Characterizing the thermo-optic coefficient of gallium phosphide-on-insulator platform using high-quality ring resonators","authors":"Weiren Cheng, Ning Ding, Xucheng Zhang, Zhenyu Liu, Xingyu Tang, Wenfu Lin, Yifan Wang, Ziyu Pan, Naiqin Bu, Mingjian You, Xingchen Ji, Yi Li, Qiancheng Zhao","doi":"10.1063/5.0258133","DOIUrl":"https://doi.org/10.1063/5.0258133","url":null,"abstract":"Characterizing a material's thermo-optic coefficient lays the foundation for optimizing thermal tuning of photonic integrated devices, a key feature for applications in optical communication, sensing, and signal processing. Unlike traditional bulk measurements, determining the thermo-optic coefficient (TOC) in microscale photonic devices offers significant advantages in data processing and provides more direct relevance to real-world device performance. In this work, we characterize the TOC of gallium phosphide (GaP) films using an air-cladded ring resonator, built on a GaP-on-insulator (GaP-OI) architecture. The resonator is fabricated via an optimized “etch-n-transfer” process, which incorporates silicon dioxide hard masks to enhance the precision of pattern transfer and improve the waveguide surface cleanliness, reducing defects and ensuring better device performance. The fabricated resonator exhibits a loaded quality factor of (2.18 ± 0.1)×104 at 1550 nm by using contact lithography, with a waveguide propagation loss of 23.8 ± 0.3 dB/cm. At 780 nm, the propagation loss decreases to 16.7 dB/cm. The resonator also shows a temperature-dependent wavelength shift of 65.8 pm/K, allowing us to extract a TOC of 1.19 × 10−4/K for GaP. This high temperature sensitivity empowers the GaP-OI platform particularly well-suited for rapid thermal turning, which is beneficial for a range of applications including optical sensing, optical signal processing, and highly efficient nonlinear conversion.","PeriodicalId":8094,"journal":{"name":"Applied Physics Letters","volume":"14 1","pages":""},"PeriodicalIF":4.0,"publicationDate":"2025-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143872394","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Fully solution-processed ferroelectric thin film transistor based on PZT and its application in neuromorphic computing

IF 4 2区物理与天体物理

Applied Physics Letters Pub Date : 2025-04-23 DOI: 10.1063/5.0263232

Yao Dong, Guangtan Miao, Wenlan Xiao, Chunyan You, Guoxia Liu, Fukai Shan

{"title":"Fully solution-processed ferroelectric thin film transistor based on PZT and its application in neuromorphic computing","authors":"Yao Dong, Guangtan Miao, Wenlan Xiao, Chunyan You, Guoxia Liu, Fukai Shan","doi":"10.1063/5.0263232","DOIUrl":"https://doi.org/10.1063/5.0263232","url":null,"abstract":"As a promising alternative to conventional computing paradigms, the neuromorphic computing has been demonstrated by using various artificial synaptic devices. Due to the excellent capability for the conductance modulation, the ferroelectric thin film transistors (FeTFTs) have been shown as one of the promising candidates for artificial synaptic devices. In this work, the FeTFTs based on the lead zirconate titanate (PZT) thin films were integrated by the fully solution process. Prior to the integration of the FeTFTs, a lanthanum nickelate (LNO) thin film was prepared as the seed layer. The introduction of the LNO has been demonstrated to improve the crystallinity of the PZT thin films. It is confirmed that the channel conductance of the FeTFTs can be precisely modulated by adjusting the amplitude, duration, and number of the pulses. The potentiation and depression (P-D) characteristics of the FeTFTs have been demonstrated, and the P-D curve shows low nonlinearity and small cycle-to-cycle variations. Based on the P-D characteristics of the FeTFTs, an artificial neural network has been constructed for the pattern recognition, and a recognition accuracy of 93.1% has been achieved. These results suggest that the fully solution-processed FeTFTs based on PZT are the promising candidate for the artificial synaptic devices.","PeriodicalId":8094,"journal":{"name":"Applied Physics Letters","volume":"42 1","pages":""},"PeriodicalIF":4.0,"publicationDate":"2025-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143872621","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Direct measurement of reduced exchange stiffness and its impact on magnetic vortex behavior in PyGd alloys

IF 4 2区物理与天体物理

Applied Physics Letters Pub Date : 2025-04-23 DOI: 10.1063/5.0256674

Liyan Jacob, Hee-Sung Han, Mi-Young Im, Shawn Pollard

{"title":"Direct measurement of reduced exchange stiffness and its impact on magnetic vortex behavior in PyGd alloys","authors":"Liyan Jacob, Hee-Sung Han, Mi-Young Im, Shawn Pollard","doi":"10.1063/5.0256674","DOIUrl":"https://doi.org/10.1063/5.0256674","url":null,"abstract":"Thin films composed of sputtered transition metal/rare earth (TM/RE) ferrimagnets have emerged as promising building blocks for future spintronic devices, offering tunable magnetic properties critical for data storage, memory, and logic applications. However, understanding how the combination of TM and RE elements influences effective magnetic properties, such as exchange stiffness (Aex), remains challenging. Magnetic vortices provide a versatile tool for probing these properties in thin film systems. By combining magnetic imaging via soft x-ray microscopy and micromagnetic modeling, we quantify the effective exchange stiffness in PyGd ferrimagnetic disks with varying Gd concentrations. Our results indicate a reduction in Aex to below 3 pJ/m for a 20% Gd concentration when compared to reference Py, and values below 2 pJ/m for 30% Gd, reflecting weak Ni–Gd exchange coupling. These findings highlight the critical role of rare earth content in tuning the exchange stiffness. The reduced exchange stiffness facilitates a linear field response of the magnetization up to the edge of the disk, as well as significant deformations in the vortex core itself when compared to films with larger Aex. Our results are in line with, albeit lower than, recent measurements of the exchange stiffness in intermixed PyGd. This reduced exchange stiffness has implications for the development of spintronic devices based on ferrimagnetic skyrmions.","PeriodicalId":8094,"journal":{"name":"Applied Physics Letters","volume":"1 1","pages":""},"PeriodicalIF":4.0,"publicationDate":"2025-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143872623","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0