npj 2D Materials and Applications最新文献_第3页

Mapping the energy-momentum dispersion of hBN excitons and hybrid plasmons in hBN-WSe2 heterostructures 绘制 hBN-WSe2 异质结构中 hBN 激子和混合质子的能量-动量频散图

IF 9.1 2区材料科学

npj 2D Materials and Applications Pub Date : 2024-10-26 DOI: 10.1038/s41699-024-00500-w

Hannah C. Nerl, Juan Pablo Guerrero-Felipe, Ana M. Valencia, Khairi Fahad Elyas, Katja Höflich, Christoph T. Koch, Caterina Cocchi

{"title":"Mapping the energy-momentum dispersion of hBN excitons and hybrid plasmons in hBN-WSe2 heterostructures","authors":"Hannah C. Nerl, Juan Pablo Guerrero-Felipe, Ana M. Valencia, Khairi Fahad Elyas, Katja Höflich, Christoph T. Koch, Caterina Cocchi","doi":"10.1038/s41699-024-00500-w","DOIUrl":"10.1038/s41699-024-00500-w","url":null,"abstract":"Heterostructures obtained by combining two-dimensional (2D) sheets are widely investigated as a platform for designing new materials with customised characteristics. Transition metal dichalcogenides (TMDCs) are often combined with hexagonal boron nitride (hBN) to enhance their excitonic resonances. However, little is known about how stacking affects excitons and plasmons in TMDCs or their mutual interactions. Here, we combine momentum-resolved electron energy-loss spectroscopy with first-principles calculations to study the energy-momentum dispersion of plasmons in multi-layer WSe2-hBN heterostructures as well as in their isolated components. The dispersion of the high-momentum excitons of hBN, alone and in combination with WSe2, is mapped across the entire Brillouin zone. Signatures of hybridisation in the plasmon resonances and some of the excitons suggest that the contribution of hBN cannot be neglected when interpreting the response of such a heterostructure. The consequences of using hBN as an encapsulant for TMDCs are also discussed.","PeriodicalId":19227,"journal":{"name":"npj 2D Materials and Applications","volume":" ","pages":"1-11"},"PeriodicalIF":9.1,"publicationDate":"2024-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.nature.com/articles/s41699-024-00500-w.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142519199","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Unraveling the influence of defects in Janus MoSSe and Janus alloys MoS2(1−x)Se2x 揭示 Janus MoSSe 和 Janus 合金 MoS2(1-x)Se2x 中缺陷的影响

IF 9.1 2区材料科学

npj 2D Materials and Applications Pub Date : 2024-10-11 DOI: 10.1038/s41699-024-00504-6

Jennifer Schmeink, Jens Osterfeld, Osamah Kharsah, Stephan Sleziona, Marika Schleberger

引用次数: 0

Author Correction: Mechanically-tunable bandgap closing in 2D graphene phononic crystals 作者更正：二维石墨烯声波晶体中可机械调控的带隙闭合

IF 9.1 2区材料科学

npj 2D Materials and Applications Pub Date : 2024-10-10 DOI: 10.1038/s41699-024-00505-5

Jan N. Kirchhof, Kirill I. Bolotin

引用次数: 0

Chalcogen and halogen surface termination coverage in MXenes—structure, stability, and properties 二甲苯中的查耳根和卤素表面终止覆盖层--结构、稳定性和特性

IF 9.1 2区材料科学

npj 2D Materials and Applications Pub Date : 2024-10-02 DOI: 10.1038/s41699-024-00502-8

Martin Dahlqvist, Johanna Rosen

{"title":"Chalcogen and halogen surface termination coverage in MXenes—structure, stability, and properties","authors":"Martin Dahlqvist, Johanna Rosen","doi":"10.1038/s41699-024-00502-8","DOIUrl":"10.1038/s41699-024-00502-8","url":null,"abstract":"MXenes are a diverse family of two-dimensional (2D) transition metal carbides, nitrides, and carbonitrides. They can be synthesized through both top-down approaches, such as selective etching of A-layers from MAX phases using acids or molten salts, and bottom-up approaches, such as direct synthesis using chemical vapor deposition. However, the degree of the surface termination coverage depends on the synthesis route and is one key parameter for controlling its properties. This study focuses on halogen- and chalcogen-terminated MXenes, particularly M2CTx where M = Ti, Zr, V, Nb, Ta, and T = S, Se, Te, Cl, Br, I, and with surface termination coverage ranging from 100% (ideal, x = 2) to 50% (x = 1). The incorporation of oxygen on vacant termination sites was also evaluated. Using density functional theory (DFT) calculations, we investigated the structural, electronic, and mechanical properties of these MXenes. Our findings reveal that non-ideal termination coverage (x < 2) is more favorable for MXenes terminated with a larger size of T, such as Ti2CBrx, Nb2CClx, and Ta2CClx, and leads to mixed termination sites and lower binding energies. A reduced binding energy may facilitate delamination into single sheets, however, too low termination coverage may also cause structural collapse. Electronic properties showed an increased number of states at the Fermi level under non-ideal coverage, potentially enhancing the conductivity. Mechanically, we find the moduli of MXenes to be comparable to other 2D materials, such as transition metal chalcogenides and hexagonal boron nitride, indicating their suitability for applications requiring flexibility and durability. This study underscores the potential of tailoring MXene properties through precise control of termination coverage and composition, paving the way for enhanced application-specific performance.","PeriodicalId":19227,"journal":{"name":"npj 2D Materials and Applications","volume":" ","pages":"1-13"},"PeriodicalIF":9.1,"publicationDate":"2024-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.nature.com/articles/s41699-024-00502-8.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142377213","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Unraveling the electronic structure and magnetic transition evolution across monolayer, bilayer, and multilayer ferromagnetic Fe3GeTe2 揭示单层、双层和多层铁磁性 Fe3GeTe2 的电子结构和磁转变演化

IF 9.1 2区材料科学

npj 2D Materials and Applications Pub Date : 2024-09-30 DOI: 10.1038/s41699-024-00499-0

R. Roemer, D. H. D. Lee, S. Smit, X. Zhang, S. Godin, V. Hamza, T. Jian, J. Larkin, H. Shin, C. Liu, M. Michiardi, G. Levy, Z. Zhang, R. J. Green, C. Kim, D. Muller, A. Damascelli, M. J. Han, K. Zou

{"title":"Unraveling the electronic structure and magnetic transition evolution across monolayer, bilayer, and multilayer ferromagnetic Fe3GeTe2","authors":"R. Roemer, D. H. D. Lee, S. Smit, X. Zhang, S. Godin, V. Hamza, T. Jian, J. Larkin, H. Shin, C. Liu, M. Michiardi, G. Levy, Z. Zhang, R. J. Green, C. Kim, D. Muller, A. Damascelli, M. J. Han, K. Zou","doi":"10.1038/s41699-024-00499-0","DOIUrl":"10.1038/s41699-024-00499-0","url":null,"abstract":"Two-dimensional (2D) van der Waals (vdW) magnets have sparked widespread attention due to their potential in spintronic applications as well as in fundamental physics. Ferromagnetic vdW compound Fe3GeTe2 (FGT) and its Ga variants have garnered significant interest due to their itinerant magnetism, correlated states, and high magnetic transition temperature. Experimental studies have demonstrated the tunability of FGT’s Curie temperature, TC, through adjustments in quintuple layer numbers (QL) and carrier concentrations, n. However, the underlying mechanism remains elusive. In this study, we employ molecular beam epitaxy (MBE) to synthesize 2D FGT films down to 1 QL with precise layer control, facilitating an exploration of the band structure and the evolution of itinerant carrier density. Angle-resolved photoemission spectroscopy (ARPES) reveals significant band structure changes at the ultra-thin limit, while first-principles calculations elucidate the band evolution from 1 QL to bulk, largely governed by interlayer coupling. Additionally, we find that n is intrinsically linked to the number of QL and temperature, with a critical value triggering the magnetic phase transition. Our findings underscore the pivotal role of band structure and itinerant electrons in governing magnetic phase transitions in such 2D vdW magnetic materials.","PeriodicalId":19227,"journal":{"name":"npj 2D Materials and Applications","volume":" ","pages":"1-8"},"PeriodicalIF":9.1,"publicationDate":"2024-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.nature.com/articles/s41699-024-00499-0.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142377215","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Phonon transport manipulation in TiSe2 via reversible charge density wave melting 通过可逆电荷密度波熔化实现 TiSe2 中的声子传输操纵

IF 9.1 2区材料科学

npj 2D Materials and Applications Pub Date : 2024-09-30 DOI: 10.1038/s41699-024-00501-9

Martí Raya-Moreno, Claudio Cazorla, Enric Canadell, Riccardo Rurali

引用次数: 0

Piezoelectricity in NbOI2 for piezotronics and nanogenerators 用于压电电子学和纳米发电机的 NbOI2 的压电性

IF 9.1 2区材料科学

npj 2D Materials and Applications Pub Date : 2024-09-16 DOI: 10.1038/s41699-024-00498-1

Yuanyuan Cui, Tingjun Wang, Deng Hu, Zhiwei Wang, Jiawang Hong, Xueyun Wang

引用次数: 0

Probing the interplay of interactions, screening and strain in monolayer MoS2 via self-intercalation 通过自插入探测单层 MoS2 中相互作用、筛选和应变的相互作用

IF 9.1 2区材料科学

npj 2D Materials and Applications Pub Date : 2024-09-12 DOI: 10.1038/s41699-024-00488-3

Borna Pielić, Matko Mužević, Dino Novko, Jiaqi Cai, Alice Bremerich, Robin Ohmann, Marko Kralj, Iva Šrut Rakić, Carsten Busse

引用次数: 0

Tailoring polarization in WSe2 quantum emitters through deterministic strain engineering 通过确定性应变工程定制 WSe2 量子发射器中的极化

IF 9.1 2区材料科学

npj 2D Materials and Applications Pub Date : 2024-09-11 DOI: 10.1038/s41699-024-00497-2

Athanasios Paralikis, Claudia Piccinini, Abdulmalik A. Madigawa, Pietro Metuh, Luca Vannucci, Niels Gregersen, Battulga Munkhbat

引用次数: 0

Metastable square Bismuth allotrope oriented by six-fold symmetric mica 六重对称云母定向的可蜕变方形铋同素异形体

IF 9.1 2区材料科学

npj 2D Materials and Applications Pub Date : 2024-09-11 DOI: 10.1038/s41699-024-00495-4

Nan Wu, Xiangchen Hu, Yinliang Tang, Congcong Wu, Yu Chen, Yiyuan Ren, Zhuo Zhang, Yi Yu, Hung-Ta Wang

{"title":"Metastable square Bismuth allotrope oriented by six-fold symmetric mica","authors":"Nan Wu, Xiangchen Hu, Yinliang Tang, Congcong Wu, Yu Chen, Yiyuan Ren, Zhuo Zhang, Yi Yu, Hung-Ta Wang","doi":"10.1038/s41699-024-00495-4","DOIUrl":"10.1038/s41699-024-00495-4","url":null,"abstract":"Layered bismuth (Bi) has been focused on two Peierls distortion derivatives, i.e., bulk stable β-phase (A7 phase), black phosphorus-like α-phase (A17 phase), and their mutated structures. Metastable structures beyond Peierls distortion system are yet rarely accessible. Here, Bi in square symmetry ( $${C}_{4v}$$ ), called s-Bi, was grown via physical vapor deposition. The co-existence of three 120°-associated s-Bi crystal grains was analyzed using transmission electron microscopy. 120°-oriented one-dimensional (1D) nuclei indicate s-Bi heteroepitaxy on six-fold symmetric ( $${C}_{6v}$$ ) mica (001). A subsequent nanorod-like nuclei coalescing could promote a morphology evolution, resulting in triangular or hexagonal nanosheets with the unique triple s-Bi structure suitable for later β-Bi growth. Lattice misfit and strain calculations suggest a supercell match between $$4times 7$$ s-Bi and $$3times 3$$ mica (001). This work demonstrates the metastable s-Bi structure via anisotropic heteroepitaxy of $${C}_{4v}$$ s-Bi on $${C}_{6v}$$ mica.","PeriodicalId":19227,"journal":{"name":"npj 2D Materials and Applications","volume":" ","pages":"1-9"},"PeriodicalIF":9.1,"publicationDate":"2024-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.nature.com/articles/s41699-024-00495-4.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142174416","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0