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

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

Engineering the electrostatic potential in a COF''s pore by selecting quadrupolar building blocks and linkages 通过选择四极结构单元和连接来设计 COF 孔隙中的静电势

IF 9.1 2区材料科学

npj 2D Materials and Applications Pub Date : 2024-09-04 DOI: 10.1038/s41699-024-00496-3

Elena-Antonella Bittner, Konrad Merkel, Frank Ortmann

{"title":"Engineering the electrostatic potential in a COF''s pore by selecting quadrupolar building blocks and linkages","authors":"Elena-Antonella Bittner, Konrad Merkel, Frank Ortmann","doi":"10.1038/s41699-024-00496-3","DOIUrl":"10.1038/s41699-024-00496-3","url":null,"abstract":"The electrostatic potential within porous materials critically influences applications like gas storage, catalysis, sensors and semiconductor technology. Precise control of this potential in covalent organic frameworks (COFs) is essential for optimizing these applications. We propose a straightforward method to achieve this by employing electric quadrupolar building blocks. Our comprehensive models accurately reproduce the electrostatic potential in 2D-COFs, requiring only a few parameters that depend solely on local electrostatic properties, independent of the COF’s lattice structure and topology. This approach has been validated across various systems, including conjugated and non-conjugated building blocks with different symmetries. We explore single-layer, few-layer, and bulk systems, achieving changes in the potential which exceed one electronvolt. Stacking configurations such as eclipsed AA, serrated AA’, and inclined stacking all exhibit the tuning effect with minor variations. Finally, we discuss the impact of these potential manipulations on applications like ion and gas uptake.","PeriodicalId":19227,"journal":{"name":"npj 2D Materials and Applications","volume":" ","pages":"1-9"},"PeriodicalIF":9.1,"publicationDate":"2024-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.nature.com/articles/s41699-024-00496-3.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142174403","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

Magnetic tunnel junction based on bilayer LaI2 as perfect spin filter device 基于双层 LaI2 的磁隧道结是完美的自旋滤波装置

IF 9.1 2区材料科学

npj 2D Materials and Applications Pub Date : 2024-09-02 DOI: 10.1038/s41699-024-00493-6

Shubham Tyagi, Avijeet Ray, Nirpendra Singh, Udo Schwingenschlögl

引用次数: 0

Electronic excitations and spin interactions in chromium trihalides from embedded many-body wavefunctions 从嵌入多体波函数看三卤化铬中的电子激发和自旋相互作用

IF 9.1 2区材料科学

npj 2D Materials and Applications Pub Date : 2024-08-30 DOI: 10.1038/s41699-024-00494-5

Ravi Yadav, Lei Xu, Michele Pizzochero, Jeroen van den Brink, Mikhail I. Katsnelson, Oleg V. Yazyev

{"title":"Electronic excitations and spin interactions in chromium trihalides from embedded many-body wavefunctions","authors":"Ravi Yadav, Lei Xu, Michele Pizzochero, Jeroen van den Brink, Mikhail I. Katsnelson, Oleg V. Yazyev","doi":"10.1038/s41699-024-00494-5","DOIUrl":"10.1038/s41699-024-00494-5","url":null,"abstract":"Although chromium trihalides are widely regarded as a promising class of two-dimensional magnets for next-generation devices, an accurate description of their electronic structure and magnetic interactions has proven challenging to achieve. Here, we quantify electronic excitations and spin interactions in CrX3 (X = Cl, Br, I) using embedded many-body wavefunction calculations and fully generalized spin Hamiltonians. We find that the three trihalides feature comparable d-shell excitations, consisting of a high-spin 4A2 $$({t}_{2g}^{3}{e}_{g}^{0})$$ ground state lying 1.5–1.7 eV below the first excited state 4T2 ( $${t}_{2g}^{2}{e}_{g}^{1}$$ ). CrCl3 exhibits a single-ion anisotropy Asia = − 0.02 meV, while the Cr spin-3/2 moments are ferromagnetically coupled through bilinear and biquadratic exchange interactions of J1 = − 0.97 meV and J2 = − 0.05 meV, respectively. The corresponding values for CrBr3 and CrI3 increase to Asia = −0.08 meV and Asia= − 0.12 meV for the single-ion anisotropy, J1 = −1.21 meV, J2 = −0.05 meV and J1 = −1.38 meV, J2 = −0.06 meV for the exchange couplings, respectively. We find that the overall magnetic anisotropy is defined by the interplay between Asia and Adip due to magnetic dipole–dipole interaction that favors in-plane orientation of magnetic moments in ferromagnetic monolayers and bulk layered magnets. The competition between the two contributions sets CrCl3 and CrI3 as the easy-plane (Asia + Adip >0) and easy-axis (Asia + Adip <0) ferromagnets, respectively. The differences between the magnets trace back to the atomic radii of the halogen ligands and the magnitude of spin–orbit coupling. Our findings are in excellent agreement with recent experiments, thus providing reference values for the fundamental interactions in chromium trihalides.","PeriodicalId":19227,"journal":{"name":"npj 2D Materials and Applications","volume":" ","pages":"1-8"},"PeriodicalIF":9.1,"publicationDate":"2024-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.nature.com/articles/s41699-024-00494-5.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142091215","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

All-2D CVD-grown semiconductor field-effect transistors with van der Waals graphene contacts 带有范德华石墨烯触点的全二维 CVD 生长半导体场效应晶体管

IF 9.1 2区材料科学

npj 2D Materials and Applications Pub Date : 2024-08-21 DOI: 10.1038/s41699-024-00489-2

Md. Anamul Hoque, Antony George, Vasudev Ramachandra, Emad Najafidehaghani, Ziyang Gan, Richa Mitra, Bing Zhao, Satyaprakash Sahoo, Maria Abrahamsson, Qiuhua Liang, Julia Wiktor, Andrey Turchanin, Sergey Kubatkin, Samuel Lara-Avila, Saroj P. Dash

{"title":"All-2D CVD-grown semiconductor field-effect transistors with van der Waals graphene contacts","authors":"Md. Anamul Hoque, Antony George, Vasudev Ramachandra, Emad Najafidehaghani, Ziyang Gan, Richa Mitra, Bing Zhao, Satyaprakash Sahoo, Maria Abrahamsson, Qiuhua Liang, Julia Wiktor, Andrey Turchanin, Sergey Kubatkin, Samuel Lara-Avila, Saroj P. Dash","doi":"10.1038/s41699-024-00489-2","DOIUrl":"10.1038/s41699-024-00489-2","url":null,"abstract":"Two-dimensional (2D) semiconductors and van der Waals (vdW) heterostructures with graphene have generated enormous interest for future electronic, optoelectronic, and energy-harvesting applications. The electronic transport properties and correlations of such hybrid devices strongly depend on the quality of the materials via chemical vapor deposition (CVD) process, their interfaces and contact properties. However, detailed electronic transport and correlation properties of the 2D semiconductor field-effect transistor (FET) with vdW graphene contacts for understanding mobility limiting factors and metal-insulator transition properties are not explored. Here, we investigate electronic transport in scalable all-2D CVD-grown molybdenum disulfide (MoS2) FET with graphene contacts. The Fermi level of graphene can be readily tuned by a gate voltage to enable a nearly perfect band alignment and, hence, a reduced and tunable Schottky barrier at the contact with good field-effect channel mobility. Detailed temperature-dependent transport measurements show dominant phonon/impurity scattering as a mobility limiting mechanisms and a gate-and bias-induced metal-insulator transition in different temperature ranges, which is explained in light of the variable-range hopping transport. These studies in such scalable all-2D semiconductor heterostructure FETs will be useful for future electronic and optoelectronic devices for a broad range of applications.","PeriodicalId":19227,"journal":{"name":"npj 2D Materials and Applications","volume":" ","pages":"1-7"},"PeriodicalIF":9.1,"publicationDate":"2024-08-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.nature.com/articles/s41699-024-00489-2.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142021838","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