1
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Zhang Y, Xiao C, Ovchinnikov D, Zhu J, Wang X, Taniguchi T, Watanabe K, Yan J, Yao W, Xu X. Every-other-layer dipolar excitons in a spin-valley locked superlattice. Nat Nanotechnol 2023; 18:501-506. [PMID: 36959300 DOI: 10.1038/s41565-023-01350-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/09/2022] [Accepted: 02/12/2023] [Indexed: 05/21/2023]
Abstract
Monolayer semiconducting transition metal dichalcogenides possess broken inversion symmetry and strong spin-orbit coupling, leading to a unique spin-valley locking effect. In 2H stacked pristine multilayers, spin-valley locking yields an electronic superlattice structure, where alternating layers correspond to barriers and quantum wells depending on the spin-valley indices. Here we show that the spin-valley locked superlattice hosts a kind of dipolar exciton with the electron and hole constituents separated in an every-other-layer configuration: that is, either in two even or two odd layers. Such excitons become optically bright via hybridization with intralayer excitons. This effect is also manifested by the presence of multiple anti-crossing patterns in the reflectance spectra, as the dipolar exciton is tuned through the intralayer resonance by an electric field. The reflectance spectra further reveal an excited state orbital of the every-other-layer exciton, pointing to a sizable binding energy in the same order of magnitude as the intralayer exciton. As layer thickness increases, the dipolar exciton can form a one-dimensional Bose-Hubbard chain displaying layer number-dependent fine spectroscopy structures.
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Affiliation(s)
- Yinong Zhang
- Department of Physics, University of Washington, Seattle, WA, USA
| | - Chengxin Xiao
- Department of Physics, University of Hong Kong, Hong Kong, China
- HKU-UCAS Joint Institute of Theoretical and Computational Physics at Hong Kong, Hong Kong, China
| | | | - Jiayi Zhu
- Department of Physics, University of Washington, Seattle, WA, USA
| | - Xi Wang
- Department of Physics, University of Washington, Seattle, WA, USA
- Department of Chemistry, University of Washington, Seattle, WA, USA
| | - Takashi Taniguchi
- International Center for Materials Nanoarchitectonics, National Institute for Materials Science, Tsukuba, Japan
| | - Kenji Watanabe
- Research Center for Functional Materials, National Institute for Materials Science, Tsukuba, Japan
| | - Jiaqiang Yan
- Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA
| | - Wang Yao
- Department of Physics, University of Hong Kong, Hong Kong, China.
- HKU-UCAS Joint Institute of Theoretical and Computational Physics at Hong Kong, Hong Kong, China.
| | - Xiaodong Xu
- Department of Physics, University of Washington, Seattle, WA, USA.
- Department of Materials Science and Engineering, University of Washington, Seattle, WA, USA.
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2
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Fonseca J, Diederich GM, Ovchinnikov D, Cai J, Wang C, Yan J, Xiao D, Xu X. Anomalous Second Harmonic Generation from Atomically Thin MnBi 2Te 4. Nano Lett 2022; 22:10134-10139. [PMID: 36475690 DOI: 10.1021/acs.nanolett.2c04010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
MnBi2Te4 is a van der Waals topological insulator with intrinsic intralayer ferromagnetic exchange and A-type antiferromagnetic interlayer coupling. Theoretically, it belongs to a class of structurally centrosymmetric crystals whose layered antiferromagnetic order breaks inversion symmetry for even layer numbers, making optical second harmonic generation (SHG) an ideal probe of the coupling between the crystal and magnetic structures. Here, we perform magnetic field and temperature-dependent SHG measurements on MnBi2Te4 flakes ranging from bulk to monolayer thickness. We find that the dominant SHG signal from MnBi2Te4 is unexpectedly unrelated to both magnetic state and layer number. We suggest that surface SHG is the likely source of the observed strong SHG, whose symmetry matches that of the MnBi2Te4-vacuum interface. Our results highlight the importance of considering the surface contribution to inversion symmetry-breaking in van der Waals centrosymmetric magnets.
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Affiliation(s)
- Jordan Fonseca
- Department of Physics, University of Washington, Seattle, Washington98195, United States
| | - Geoffrey M Diederich
- Department of Physics, University of Washington, Seattle, Washington98195, United States
- Intelligence Community Postdoctoral Research Fellowship Program, University of Washington, Seattle, Washington98195, United States
| | - Dmitry Ovchinnikov
- Department of Physics, University of Washington, Seattle, Washington98195, United States
| | - Jiaqi Cai
- Department of Physics, University of Washington, Seattle, Washington98195, United States
| | - Chong Wang
- Department of Materials Science and Engineering, University of Washington, Seattle, Washington98195, United States
| | - Jiaqiang Yan
- Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee37831, United States
- Department of Materials Science and Engineering, University of Tennessee, Knoxville, Tennessee37996, United States
| | - Di Xiao
- Department of Physics, University of Washington, Seattle, Washington98195, United States
- Department of Materials Science and Engineering, University of Washington, Seattle, Washington98195, United States
| | - Xiaodong Xu
- Department of Physics, University of Washington, Seattle, Washington98195, United States
- Department of Materials Science and Engineering, University of Washington, Seattle, Washington98195, United States
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3
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Cai J, Ovchinnikov D, Fei Z, He M, Song T, Lin Z, Wang C, Cobden D, Chu JH, Cui YT, Chang CZ, Xiao D, Yan J, Xu X. Electric control of a canted-antiferromagnetic Chern insulator. Nat Commun 2022; 13:1668. [PMID: 35351900 PMCID: PMC8964814 DOI: 10.1038/s41467-022-29259-8] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2021] [Accepted: 03/07/2022] [Indexed: 11/17/2022] Open
Abstract
The interplay between band topology and magnetism can give rise to exotic states of matter. For example, magnetically doped topological insulators can realize a Chern insulator that exhibits quantized Hall resistance at zero magnetic field. While prior works have focused on ferromagnetic systems, little is known about band topology and its manipulation in antiferromagnets. Here, we report that MnBi2Te4 is a rare platform for realizing a canted-antiferromagnetic (cAFM) Chern insulator with electrical control. We show that the Chern insulator state with Chern number C = 1 appears as the AFM to canted-AFM phase transition happens. The Chern insulator state is further confirmed by observing the unusual transition of the C = 1 state in the cAFM phase to the C = 2 orbital quantum Hall states in the magnetic field induced ferromagnetic phase. Near the cAFM-AFM phase boundary, we show that the dissipationless chiral edge transport can be toggled on and off by applying an electric field alone. We attribute this switching effect to the electrical field tuning of the exchange gap alignment between the top and bottom surfaces. Our work paves the way for future studies on topological cAFM spintronics and facilitates the development of proof-of-concept Chern insulator devices. Exotic states emerge from the interplay between band topology and ferromagnetism, but it remains less known in canted-antiferromagnetic phase. Here, the authors realize a canted-antiferromagnetic Chern insulator in atomically-thin MnBi2Te4 with electrical control of chiral-edge state transport.
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4
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Zhao YF, Zhou LJ, Wang F, Wang G, Song T, Ovchinnikov D, Yi H, Mei R, Wang K, Chan MHW, Liu CX, Xu X, Chang CZ. Even-Odd Layer-Dependent Anomalous Hall Effect in Topological Magnet MnBi 2Te 4 Thin Films. Nano Lett 2021; 21:7691-7698. [PMID: 34468149 DOI: 10.1021/acs.nanolett.1c02493] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Recently, MnBi2Te4 has been demonstrated to be an intrinsic magnetic topological insulator and the quantum anomalous Hall (QAH) effect was observed in exfoliated MnBi2Te4 flakes. Here, we used molecular beam epitaxy (MBE) to grow MnBi2Te4 films with thickness down to 1 septuple layer (SL) and performed thickness-dependent transport measurements. We observed a nonsquare hysteresis loop in the antiferromagnetic state for films with thickness greater than 2 SL. The hysteresis loop can be separated into two AH components. We demonstrated that one AH component with the larger coercive field is from the dominant MnBi2Te4 phase, whereas the other AH component with the smaller coercive field is from the minor Mn-doped Bi2Te3 phase. The extracted AH component of the MnBi2Te4 phase shows a clear even-odd layer-dependent behavior. Our studies reveal insights on how to optimize the MBE growth conditions to improve the quality of MnBi2Te4 films.
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Affiliation(s)
- Yi-Fan Zhao
- Department of Physics, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Ling-Jie Zhou
- Department of Physics, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Fei Wang
- Department of Physics, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Guang Wang
- Department of Physics, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Tiancheng Song
- Department of Physics, University of Washington, Seattle, Washington 98195, United States
| | - Dmitry Ovchinnikov
- Department of Physics, University of Washington, Seattle, Washington 98195, United States
| | - Hemian Yi
- Department of Physics, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Ruobing Mei
- Department of Physics, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Ke Wang
- Material Research Institute, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Moses H W Chan
- Department of Physics, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Chao-Xing Liu
- Department of Physics, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Xiaodong Xu
- Department of Physics, University of Washington, Seattle, Washington 98195, United States
- Department of Material Science and Engineering, University of Washington, Seattle, Washington 98195, United States
| | - Cui-Zu Chang
- Department of Physics, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
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5
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Ovchinnikov D, Huang X, Lin Z, Fei Z, Cai J, Song T, He M, Jiang Q, Wang C, Li H, Wang Y, Wu Y, Xiao D, Chu JH, Yan J, Chang CZ, Cui YT, Xu X. Intertwined Topological and Magnetic Orders in Atomically Thin Chern Insulator MnBi 2Te 4. Nano Lett 2021; 21:2544-2550. [PMID: 33710884 DOI: 10.1021/acs.nanolett.0c05117] [Citation(s) in RCA: 52] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
MnBi2Te4, a van der Waals magnet, is an emergent platform for exploring Chern insulator physics. Its layered antiferromagnetic order was predicted to enable even-odd layer number dependent topological states. Furthermore, it becomes a Chern insulator when all spins are aligned by an applied magnetic field. However, the evolution of the bulk electronic structure as the magnetic state is continuously tuned and its dependence on layer number remains unexplored. Here, employing multimodal probes, we establish one-to-one correspondence between bulk electronic structure, magnetic state, topological order, and layer thickness in atomically thin MnBi2Te4 devices. As the magnetic state is tuned through the canted magnetic phase, we observe a band crossing, i.e., the closing and reopening of the bulk band gap, corresponding to the concurrent topological phase transition in both even- and odd-layer-number devices. Our findings shed new light on the interplay between band topology and magnetic order in this newly discovered topological magnet.
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Affiliation(s)
- Dmitry Ovchinnikov
- Department of Physics, University of Washington, Seattle, Washington 98195, United States
| | - Xiong Huang
- Department of Physics and Astronomy, University of California, Riverside, California 92521, United States
- Department of Materials Science and Engineering, University of California, Riverside, California 92521, United States
| | - Zhong Lin
- Department of Physics, University of Washington, Seattle, Washington 98195, United States
| | - Zaiyao Fei
- Department of Physics, University of Washington, Seattle, Washington 98195, United States
| | - Jiaqi Cai
- Department of Physics, University of Washington, Seattle, Washington 98195, United States
| | - Tiancheng Song
- Department of Physics, University of Washington, Seattle, Washington 98195, United States
| | - Minhao He
- Department of Physics, University of Washington, Seattle, Washington 98195, United States
| | - Qianni Jiang
- Department of Physics, University of Washington, Seattle, Washington 98195, United States
| | - Chong Wang
- Department of Physics, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States
| | - Hao Li
- School of Materials Science and Engineering, Tsinghua University, Beijing, 100084, People's Republic of China
| | - Yayu Wang
- Department of Physics, Tsinghua University, Beijing 100084, People's Republic of China
| | - Yang Wu
- Department of Mechanical Engineering, Tsinghua University, Beijing 100084, People's Republic of China
| | - Di Xiao
- Department of Physics, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States
| | - Jiun-Haw Chu
- Department of Physics, University of Washington, Seattle, Washington 98195, United States
| | - Jiaqiang Yan
- Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
- Department of Materials Science and Engineering, University of Tennessee, Knoxville, Tennessee 37996, United States
| | - Cui-Zu Chang
- Department of Physics, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Yong-Tao Cui
- Department of Physics and Astronomy, University of California, Riverside, California 92521, United States
| | - Xiaodong Xu
- Department of Physics, University of Washington, Seattle, Washington 98195, United States
- Department of Materials Science and Engineering, University of Washington, Seattle, Washington 98195, United States
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6
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Boureau V, Sklenard B, McLeod R, Ovchinnikov D, Dumcenco D, Kis A, Cooper D. Quantitative Mapping of the Charge Density in a Monolayer of MoS 2 at Atomic Resolution by Off-Axis Electron Holography. ACS Nano 2020; 14:524-530. [PMID: 31820927 DOI: 10.1021/acsnano.9b06716] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
The electric potential, electric field, and charge density of a monolayer of MoS2 have been quantitatively measured at atomic-scale resolution. This has been performed by off-axis electron holography using a double aberration-corrected transmission electron microscope operated at 80 kV and a low electron beam current density. Using this low dose rate and acceleration voltage, the specimen damage is limited during imaging. In order to improve the sensitivity of the measurement, a series of holograms have been acquired. Instabilities of the microscope such as the drifts of the specimen, biprism, and optical aberrations during the acquisition have been corrected by data processing. Phase images of the MoS2 monolayer have been acquired with a sensitivity of 2π/698 rad associated with a spatial resolution of 2.4 Å. The improvement in the signal-to-noise ratio allows the charge density to be directly calculated from the phase images using Poisson's equation. Density functional theory simulations of the potential and charge density of this MoS2 monolayer were performed for comparison to the experiment. The experimental measurements and simulations are consistent with each other, and notably, the charge density in a sulfur monovacancy (VS) site is shown.
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Affiliation(s)
- Victor Boureau
- Université Grenoble Alpes, CEA, LETI , F-38054 Grenoble , France
| | - Benoit Sklenard
- Université Grenoble Alpes, CEA, LETI , F-38054 Grenoble , France
| | - Robert McLeod
- Université Grenoble Alpes, CEA, INAC , F-38054 Grenoble , France
| | - Dmitry Ovchinnikov
- Electrical Engineering Institute , Ecole Polytechnique Federale de Lausanne , CH-1015 Lausanne , Switzerland
| | - Dumitru Dumcenco
- Electrical Engineering Institute , Ecole Polytechnique Federale de Lausanne , CH-1015 Lausanne , Switzerland
| | - Andras Kis
- Electrical Engineering Institute , Ecole Polytechnique Federale de Lausanne , CH-1015 Lausanne , Switzerland
| | - David Cooper
- Université Grenoble Alpes, CEA, LETI , F-38054 Grenoble , France
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7
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May AF, Ovchinnikov D, Zheng Q, Hermann R, Calder S, Huang B, Fei Z, Liu Y, Xu X, McGuire MA. Ferromagnetism Near Room Temperature in the Cleavable van der Waals Crystal Fe 5GeTe 2. ACS Nano 2019; 13:4436-4442. [PMID: 30865426 DOI: 10.1021/acsnano.8b09660] [Citation(s) in RCA: 95] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Two-dimensional materials with intrinsic functionality are becoming increasingly important in exploring fundamental condensed matter science and for developing advanced technologies. Bulk crystals that can be exfoliated are particularly relevant to these pursuits as they provide the opportunity to study the role of physical dimensionality and explore device physics in highly crystalline samples and designer heterostructures in a routine manner. Magnetism is a key element in these endeavors; however, relatively few cleavable materials are magnetic and none possess magnetic order at ambient conditions. Here, we introduce Fe5- xGeTe2 as a cleavable material with ferromagnetic behavior at room temperature. We established intrinsic magnetic order at room temperature in bulk crystals ([Formula: see text] = 310 K) through magnetization measurements and in exfoliated, thin flakes ([Formula: see text] ≈ 280 K) using the anomalous Hall effect. Our work reveals Fe5GeTe2 as a prime candidate for incorporating intrinsic magnetism into functional van der Waals heterostructures and devices near room temperature.
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Affiliation(s)
- Andrew F May
- Materials Science and Technology Division , Oak Ridge National Laboratory , Oak Ridge , Tennessee 37831 , United States
| | - Dmitry Ovchinnikov
- Department of Physics , University of Washington , Seattle , Washington 98195 , United States
| | - Qiang Zheng
- Materials Science and Technology Division , Oak Ridge National Laboratory , Oak Ridge , Tennessee 37831 , United States
| | - Raphael Hermann
- Materials Science and Technology Division , Oak Ridge National Laboratory , Oak Ridge , Tennessee 37831 , United States
| | - Stuart Calder
- Neutron Scattering Division , Oak Ridge National Laboratory , Oak Ridge , Tennessee 37831 , United States
| | - Bevin Huang
- Department of Physics , University of Washington , Seattle , Washington 98195 , United States
| | - Zaiyao Fei
- Department of Physics , University of Washington , Seattle , Washington 98195 , United States
| | - Yaohua Liu
- Neutron Scattering Division , Oak Ridge National Laboratory , Oak Ridge , Tennessee 37831 , United States
| | - Xiaodong Xu
- Department of Physics , University of Washington , Seattle , Washington 98195 , United States
- Department of Materials Science and Engineering , University of Washington , Seattle , Washington 98195 , United States
| | - Michael A McGuire
- Materials Science and Technology Division , Oak Ridge National Laboratory , Oak Ridge , Tennessee 37831 , United States
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8
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Requena J, Alvarez-Palomo AB, Codina-Pascual M, Delgado-Morales R, Moran S, Esteller M, Sal M, Juan M, Boronat Barado A, Consiglio A, Bogle OA, Wolvetang E, Ovchinnikov D, Alvarez I, Jaraquemada D, Mezquita-Pla J, Oliva R, Edel MJ. Global Proteomic and Methylome Analysis in Human Induced Pluripotent Stem Cells Reveals Overexpression of a Human TLR3 Affecting Proper Innate Immune Response Signaling. Stem Cells 2019; 37:476-488. [PMID: 30664289 PMCID: PMC6487958 DOI: 10.1002/stem.2966] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2018] [Revised: 11/17/2018] [Accepted: 12/21/2018] [Indexed: 12/12/2022]
Abstract
When considering the clinical applications of autologous cell replacement therapy of human induced pluripotent stem cells (iPSC)‐derived cells, there is a clear need to better understand what the immune response will be before we embark on extensive clinical trials to treat or model human disease. We performed a detailed assessment comparing human fibroblast cell lines (termed F1) reprogrammed into human iPSC and subsequently differentiated back to fibroblast cells (termed F2) or other human iPSC‐derived cells including neural stem cells (NSC) made from either retroviral, episomal, or synthetic mRNA cell reprogramming methods. Global proteomic analysis reveals the main differences in signal transduction and immune cell protein expression between F1 and F2 cells, implicating wild type (WT) toll like receptor protein 3 (TLR3). Furthermore, global methylome analysis identified an isoform of the human TLR3 gene that is not epigenetically reset correctly upon differentiation to F2 cells resulting in a hypomethylated transcription start site in the TLR3 isoform promoter and overexpression in most human iPSC‐derived cells not seen in normal human tissue. The human TLR3 isoform in human iPSC‐NSC functions to suppress NF‐KB p65 signaling pathway in response to virus (Poly IC), suggesting suppressed immunity of iPSC‐derived cells to viral infection. The sustained WT TLR3 and TLR3 isoform overexpression is central to understanding the altered immunogenicity of human iPSC‐derived cells calling for screening of human iPSC‐derived cells for TLR3 expression levels before applications. stem cells2019;37:476–488
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Affiliation(s)
- Jordi Requena
- Molecular Genetics and Control of Pluripotency Laboratory, Faculty of Medicine, Department of Biomedicine, University of Barcelona, Barcelona, Spain
| | - Ana Belen Alvarez-Palomo
- Molecular Genetics and Control of Pluripotency Laboratory, Faculty of Medicine, Department of Biomedicine, University of Barcelona, Barcelona, Spain
| | - Montserrat Codina-Pascual
- Genetics Unit, Department of Biomedicine, Faculty of Medicine, University of Barcelona, IDIBAPS and Hospital Clinic, Barcelona, Spain
| | - Raul Delgado-Morales
- Cancer Epigenetics and Biology Program (PEBC), Bellvitge Biomedical Research Institute (IDIBELL), L'Hospitalet de Llobregat, Barcelona, Catalonia, Spain.,Department of Psychiatry & Neuropsychology, School for Mental Health and Neuroscience (MHeNs), Maastricht University, Maastricht, The Netherlands
| | - Sebastian Moran
- Cancer Epigenetics and Biology Program (PEBC), Bellvitge Biomedical Research Institute (IDIBELL), L'Hospitalet de Llobregat, Barcelona, Catalonia, Spain
| | - Manel Esteller
- Cancer Epigenetics and Biology Program (PEBC), Bellvitge Biomedical Research Institute (IDIBELL), L'Hospitalet de Llobregat, Barcelona, Catalonia, Spain.,Department of Biomedicine, School of Medicine, University of Barcelona, Barcelona, Catalonia, Spain.,Institució Catalana de Recerca i Estudis Avançats (ICREA), Barcelona, Catalonia, Spain
| | - Martí Sal
- Molecular Genetics and Control of Pluripotency Laboratory, Faculty of Medicine, Department of Biomedicine, University of Barcelona, Barcelona, Spain
| | - Manel Juan
- Service of Immunology, Hospital Clinic, Hospital Sant Joan de Déu, Barcelona, Spain
| | - Anna Boronat Barado
- Service of Immunology, Hospital Clinic, Hospital Sant Joan de Déu, Barcelona, Spain
| | - Antonella Consiglio
- Department of Pathology and Experimental Therapeutics, Bellvitge University Hospital-IDIBELL, Hospitalet de Llobregat 08908, Spain.,Institute of Biomedicine of the University of Barcelona (IBUB), Barcelona 08028, Spain.,Department of Molecular and Translational Medicine, University of Brescia, Brescia 25121, Italy
| | - Orleigh Addeleccia Bogle
- Genetics Unit, Department of Biomedicine, Faculty of Medicine, University of Barcelona, IDIBAPS and Hospital Clinic, Barcelona, Spain
| | - Ernst Wolvetang
- Stem Cell Engineering Group, Australian Institute for Bioengineering and Nanotechnology, University of Queensland, Queensland, Brisbane, Australia
| | - Dmitry Ovchinnikov
- Stem Cell Engineering Group, Australian Institute for Bioengineering and Nanotechnology, University of Queensland, Queensland, Brisbane, Australia
| | - Inaki Alvarez
- Immunology Unit, Department of Cell Biology, Physiology and Immunology and Institute of Biotechnology and Biomedicine, Autonomous University of Barcelona, Bellaterra, Spain
| | - Dolores Jaraquemada
- Immunology Unit, Department of Cell Biology, Physiology and Immunology and Institute of Biotechnology and Biomedicine, Autonomous University of Barcelona, Bellaterra, Spain
| | - Jovita Mezquita-Pla
- Molecular Genetics and Control of Pluripotency Laboratory, Faculty of Medicine, Department of Biomedicine, University of Barcelona, Barcelona, Spain.,Department of Biomedicine, School of Medicine, University of Barcelona, Barcelona, Catalonia, Spain
| | - Rafael Oliva
- Genetics Unit, Department of Biomedicine, Faculty of Medicine, University of Barcelona, IDIBAPS and Hospital Clinic, Barcelona, Spain.,Department of Biomedicine, School of Medicine, University of Barcelona, Barcelona, Catalonia, Spain
| | - Michael J Edel
- Molecular Genetics and Control of Pluripotency Laboratory, Faculty of Medicine, Department of Biomedicine, University of Barcelona, Barcelona, Spain.,Department of Physiology, Anatomy and Genetics, Oxford University, Oxford, United Kingdom
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9
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García-Azorin D, Yamani N, Messina LM, Peeters I, Ferilli MAN, Ovchinnikov D, Speranza ML, Marini V, Negro A, Benemei S, Barloese M. Correction to: A PRISMA-compliant systematic review of the endpoints employed to evaluate symptomatic treatments for primary headaches. J Headache Pain 2019; 20:14. [PMID: 30760196 PMCID: PMC6734367 DOI: 10.1186/s10194-019-0967-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2019] [Accepted: 01/30/2019] [Indexed: 11/25/2022] Open
Affiliation(s)
- D García-Azorin
- Headache Unit Neurology Department, Hospital Clínico Universitario Valladolid, Avda. Ramón y Cajal 3, 47005, Valladolid, Spain.
| | - N Yamani
- Danish Headache Centre and Department of Neurology, University of Copenhagen, Rigshospitalet Glostrup, Copenhagen, Denmark.,Headache Department, Iranian Center of Neurological Research Neuroscience Institute, Tehran University of Medical Sciences, Tehran, Iran
| | - L M Messina
- Child Neuropsychiatry School, University of Palermo, Palermo, Italy.,U.O. Neuropsychiatry - ARNAS Civico, PO Di Cristina, Palermo, Italy
| | - I Peeters
- Neurology Department, University Hospital of Brussels, Brussels, Belgium
| | - M A N Ferilli
- Headache Center, Bambino Gesù Children Hospital IRCCS, Rome, Italy
| | - D Ovchinnikov
- Pavlov First Saint Petersburg State Medical University, Saint Petesburg, Russia.,Almazov National Medical Research Centre, Saint Petesburg, Russia
| | - M L Speranza
- Internal Medicine Department, Sant'Andrea Hospital, Rome, Italy
| | - V Marini
- Internal Medicine Department, Sant'Andrea Hospital, Rome, Italy
| | - A Negro
- Regional Referral Headache Centre, Department of Clinical and Molecular Medicine, Sant'Andrea Hospital, Sapienza University, Rome, Italy
| | - S Benemei
- Headache Centre, Careggi University Hospital, University of Florence, Florence, Italy
| | - M Barloese
- Danish Headache Center, Department of Neurology, Rigshospitalet-Glostrup, University of Copenhagen, Copenhagen, Denmark.,Department of Clinical Physiology and Nuclear Medicine, Center for Functional and Diagnostic Imaging, Hvidovre Hospital, Copenhagen, Denmark
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10
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Alateeq S, Ovchinnikov D, Tracey T, Whitworth D, Al-Rubaish A, Al-Ali A, Wolvetang E. Identification of on-target mutagenesis during correction of a beta-thalassemia splice mutation in iPS cells with optimised CRISPR/Cas9-double nickase reveals potential safety concerns. APL Bioeng 2018; 2:046103. [PMID: 31069325 PMCID: PMC6481731 DOI: 10.1063/1.5048625] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2018] [Accepted: 11/05/2018] [Indexed: 12/15/2022] Open
Abstract
Precise and accurate gene correction is crucial for enabling iPSC-based therapies, and Cas9-Nickase based approaches are increasingly considered for in vivo correction of diseases such as beta-thalassemia. Here, we generate footprint-free induced pluripotent stem cells from a patient with a beta-thalassemia mutation (IVSII-1 G > A) and employ a double Cas9nickase-mediated correction strategy combined with a piggyBac transposon-modified donor vector for gene correction. Our approach further aimed to minimize the formation of adjacent single-strand breaks at the targeted allele through the destruction of the binding site for one guide and the use of a synonymous protospacer adjacent motif blocking mutation (canonical PAM sequence 5'-NGG-3' is changed to 5'-NCG-3', where N indicates any nucleobase) for the other guide. We show that this strategy indeed not only permits bi-allelic seamless repair of the beta-globin gene splice site mutation and negligible off-target mutagenesis or re-editing of the targeted allele but also results in unexpected on-target mutagenesis with some guide RNAs (gRNAs) in several targeted clones. This study thus not only validates a framework for seamless gene correction with enhanced specificity and accuracy but also highlights potential safety concerns associated with Cas9-nickase based gene correction.
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Affiliation(s)
| | - Dmitry Ovchinnikov
- Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, St Lucia, QLD 4072, Australia
| | - Timothy Tracey
- Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, St Lucia, QLD 4072, Australia
| | - Deanne Whitworth
- School of Veterinary Science, The University of Queensland, Gatton, QLD 4343, Australia
| | - Abdullah Al-Rubaish
- Department of Internal Medicine, College of Medicine, King Fahd Hospital of the University, Imam Abdulrahman Bin Faisal University, Dammam 31451, Kingdom of Saudi Arabia
| | - Amein Al-Ali
- Department of Biochemistry, College of Medicine, Imam Abdulrahman Bin Faisal University, Dammam 31451, Kingdom of Saudi Arabia
| | - Ernst Wolvetang
- Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, St Lucia, QLD 4072, Australia
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11
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García-Azorin D, Yamani N, Messina LM, Peeters I, Ferrili M, Ovchinnikov D, Speranza ML, Marini V, Negro A, Benemei S, Barloese M. A PRISMA-compliant systematic review of the endpoints employed to evaluate symptomatic treatments for primary headaches. J Headache Pain 2018; 19:90. [PMID: 30242571 PMCID: PMC6742919 DOI: 10.1186/s10194-018-0920-9] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2018] [Accepted: 09/14/2018] [Indexed: 01/21/2023] Open
Abstract
BACKGROUND Primary headache are prevalent and debilitating disorders. Acute pain cessation is one of the key points in their treatment. Many drugs have been studied but the design of the trials is not usually homogeneous. Efficacy of the trial is determined depending on the selected primary endpoint and usually other different outcomes are measured. We aim to critically appraise which were the employed outcomes through a systematic review. METHODS We conducted a systematic review of literature focusing on studies on primary headache evaluating acute relief of pain, following the PRISMA guideline. The study population included patients participating in a controlled study about symptomatic treatment. The comparator could be placebo or the standard of care. The collected information was the primary outcome of the study and all secondary outcomes. We evaluated the studied drug, the year of publication and the type of journal. We performed a search and we screened all the potential papers and reviewed them considering inclusion/exclusion criteria. RESULTS The search showed 4288 clinical trials that were screened and 794 full articles were assessed for eligibility for a final inclusion of 495 papers. The studies were published in headache specific journals (58%), general journals (21.6%) and neuroscience journals (20.4%). Migraine was the most studied headache, in 87.8% studies, followed by tension type headache in 4.7%. Regarding the most evaluated drug, triptans represented 68.6% of all studies, followed by non-steroidal anti-inflammatories (25.1%). Only 4.6% of the papers evaluated ergots and 1.6% analyzed opioids. The most frequent primary endpoint was the relief of the headache at a determinate moment, in 54.1%. Primary endpoint was evaluated at 2-h in 69.9% of the studies. Concerning other endpoints, tolerance was the most frequently addressed (83%), followed by headache relief (71.1%), improvement of other symptoms (62.5%) and presence of relapse (54%). The number of secondary endpoints increased from 4.2 (SD = 2.0) before 1991 to 6.39 after 2013 (p = 0.001). CONCLUSION Headache relief has been the most employed primary endpoint but headache disappearance starts to be firmly considered. The number of secondary endpoints increases over time and other outcomes such as disability, quality of life and patients' preference are receiving attention.
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Affiliation(s)
- D. García-Azorin
- Headache Unit Neurology Department, Hospital Clínico Universitario Valladolid, Avda. Ramón y Cajal 3, 47005 Valladolid, Spain
| | - N. Yamani
- Danish Headache Centre and Department of Neurology, University of Copenhagen, Rigshospitalet Glostrup, Copenhagen, Denmark
- Headache Department, Iranian Center of Neurological Research Neuroscience Institute, Tehran University of Medical Sciences, Tehran, Iran
| | - L. M. Messina
- Child Neuropsychiatry School, University of Palermo, Palermo, Italy
- U.O. Neuropsychiatry - ARNAS Civico, PO Di Cristina, Palermo, Italy
| | - I. Peeters
- Neurology Department, University Hospital of Brussels, Brussels, Belgium
| | - M. Ferrili
- Headache Center, Bambino Gesù Children Hospital IRCCS, Rome, Italy
| | - D. Ovchinnikov
- Pavlov First Saint Petersburg State Medical University, Saint Petesburg, Russia
- Almazov National Medical Research Centre, Saint Petesburg, Russia
| | - M. L. Speranza
- Internal Medicine Department, Sant’Andrea Hospital, Rome, Italy
| | - V. Marini
- Internal Medicine Department, Sant’Andrea Hospital, Rome, Italy
| | - A. Negro
- Regional Referral Headache Centre, Sant’Andrea Hospital, Department of Clinical and Molecular Medicine, Sapienza University, Rome, Italy
| | - S. Benemei
- Headache Centre, Careggi University Hospital, University of Florence, Florence, Italy
| | - M. Barloese
- Danish Headache Center, Department of Neurology, Rigshospitalet-Glostrup, University of Copenhagen, Copenhagen, Denmark
- Department of Clinical Physiology and Nuclear Medicine, Center for Functional and Diagnostic Imaging, Hvidovre Hospital, Copenhagen, Denmark
| | - on behalf of the European Headache Federation School of Advanced Studies (EHF-SAS)
- Headache Unit Neurology Department, Hospital Clínico Universitario Valladolid, Avda. Ramón y Cajal 3, 47005 Valladolid, Spain
- Danish Headache Centre and Department of Neurology, University of Copenhagen, Rigshospitalet Glostrup, Copenhagen, Denmark
- Headache Department, Iranian Center of Neurological Research Neuroscience Institute, Tehran University of Medical Sciences, Tehran, Iran
- Child Neuropsychiatry School, University of Palermo, Palermo, Italy
- U.O. Neuropsychiatry - ARNAS Civico, PO Di Cristina, Palermo, Italy
- Neurology Department, University Hospital of Brussels, Brussels, Belgium
- Headache Center, Bambino Gesù Children Hospital IRCCS, Rome, Italy
- Pavlov First Saint Petersburg State Medical University, Saint Petesburg, Russia
- Almazov National Medical Research Centre, Saint Petesburg, Russia
- Internal Medicine Department, Sant’Andrea Hospital, Rome, Italy
- Regional Referral Headache Centre, Sant’Andrea Hospital, Department of Clinical and Molecular Medicine, Sapienza University, Rome, Italy
- Headache Centre, Careggi University Hospital, University of Florence, Florence, Italy
- Danish Headache Center, Department of Neurology, Rigshospitalet-Glostrup, University of Copenhagen, Copenhagen, Denmark
- Department of Clinical Physiology and Nuclear Medicine, Center for Functional and Diagnostic Imaging, Hvidovre Hospital, Copenhagen, Denmark
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12
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Hidalgo A, Glass N, Ovchinnikov D, Yang SK, Zhang X, Mazzone S, Chen C, Wolvetang E, Cooper-White J. Modelling ischemia-reperfusion injury (IRI) in vitro using metabolically matured induced pluripotent stem cell-derived cardiomyocytes. APL Bioeng 2018; 2:026102. [PMID: 31069299 PMCID: PMC6481709 DOI: 10.1063/1.5000746] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2017] [Accepted: 02/27/2018] [Indexed: 12/31/2022] Open
Abstract
Coronary intervention following ST-segment elevation myocardial infarction (STEMI) is the treatment of choice for reducing cardiomyocyte death but paradoxically leads to reperfusion injury. Pharmacological post-conditioning is an attractive approach to minimize Ischemia-Reperfusion Injury (IRI), but candidate drugs identified in IRI animal models have performed poorly in human clinical trials, highlighting the need for a human cell-based model of IRI. In this work, we show that when we imposed sequential hypoxia and reoxygenation episodes [mimicking the ischemia (I) and reperfusion (R) events] to immature human pluripotent stem cell-derived cardiomyocytes (hPSC-CMs), they display significant hypoxia resistance and minimal cell death (∼5%). Metabolic maturation of hPSC-CMs for 8 days substantially increased their sensitivity to changes in oxygen concentration and led to up to ∼30% cell death post-hypoxia and reoxygenation. To mimic the known transient changes in the interstitial tissue microenvironment during an IRI event in vivo, we tested a new in vitro IRI model protocol that required glucose availability and lowering of media pH during the ischemic episode, resulting in a significant increase in cell death in vitro (∼60%). Finally, we confirm that in this new physiologically matched IRI in vitro model, pharmacological post-conditioning reduces reperfusion-induced hPSC-CM cell death by 50%. Our results indicate that in recapitulating key aspects of an in vivo IRI event, our in vitro model can serve as a useful method for the study of IRI and the validation and screening of human specific pharmacological post-conditioning drug candidates.
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Affiliation(s)
| | - Nick Glass
- Tissue Engineering and Microfluidics Group, Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, Brisbane 4072, Australia
| | - Dmitry Ovchinnikov
- Stem Cell Engineering Group, Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, Brisbane 4072, Australia
| | - Seung-Kwon Yang
- Laboratory for Respiratory Neuroscience and Mucosal Immunity, School of Biomedical Sciences, The University of Queensland, St. Lucia 4072, Australia
| | - Xinli Zhang
- Laboratory for Endocrinology and Metabolism, School of Biomedical Sciences, The University of Queensland, St. Lucia 4072, Australia
| | - Stuart Mazzone
- Laboratory for Respiratory Neuroscience and Mucosal Immunity, School of Biomedical Sciences, The University of Queensland, St. Lucia 4072, Australia
| | - Chen Chen
- Laboratory for Endocrinology and Metabolism, School of Biomedical Sciences, The University of Queensland, St. Lucia 4072, Australia
| | - Ernst Wolvetang
- Stem Cell Engineering Group, Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, Brisbane 4072, Australia
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13
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Ciarrocchi A, Avsar A, Ovchinnikov D, Kis A. Thickness-modulated metal-to-semiconductor transformation in a transition metal dichalcogenide. Nat Commun 2018; 9:919. [PMID: 29500434 PMCID: PMC5834615 DOI: 10.1038/s41467-018-03436-0] [Citation(s) in RCA: 91] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2018] [Accepted: 02/13/2018] [Indexed: 11/09/2022] Open
Abstract
The possibility of tailoring physical properties by changing the number of layers in van der Waals crystals is one of the driving forces behind the emergence of two-dimensional materials. One example is bulk MoS2, which changes from an indirect gap semiconductor to a direct bandgap semiconductor in the monolayer form. Here, we show a much bigger tuning range with a complete switching from a metal to a semiconductor in atomically thin PtSe2 as its thickness is reduced. Crystals with a thickness of ~13 nm show metallic behavior with a contact resistance as low as 70 Ω·µm. As they are thinned down to 2.5 nm and below, we observe semiconducting behavior. In such thin crystals, we demonstrate ambipolar transport with a bandgap smaller than 2.2 eV and an on/off ratio of ~105. Our results demonstrate that PtSe2 possesses an unusual behavior among 2D materials, enabling novel applications in nano and optoelectronics.
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Affiliation(s)
- Alberto Ciarrocchi
- Electrical Engineering Institute, École Polytechnique Fédérale de Lausanne (EPFL), 1015, Lausanne, Switzerland
- Institute of Materials Science and Engineering, École Polytechnique Fédérale de Lausanne (EPFL), 1015, Lausanne, Switzerland
| | - Ahmet Avsar
- Electrical Engineering Institute, École Polytechnique Fédérale de Lausanne (EPFL), 1015, Lausanne, Switzerland
- Institute of Materials Science and Engineering, École Polytechnique Fédérale de Lausanne (EPFL), 1015, Lausanne, Switzerland
| | - Dmitry Ovchinnikov
- Electrical Engineering Institute, École Polytechnique Fédérale de Lausanne (EPFL), 1015, Lausanne, Switzerland
- Institute of Materials Science and Engineering, École Polytechnique Fédérale de Lausanne (EPFL), 1015, Lausanne, Switzerland
| | - Andras Kis
- Electrical Engineering Institute, École Polytechnique Fédérale de Lausanne (EPFL), 1015, Lausanne, Switzerland.
- Institute of Materials Science and Engineering, École Polytechnique Fédérale de Lausanne (EPFL), 1015, Lausanne, Switzerland.
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14
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Ovchinnikov D, Garnyuk V, Vorobiev E, Beltiukov P, Grebennik V, Gordeev M, Barantsevich E. Postoperative cognitive decline after CABG -- association between cytokines profile and matrix metalloproteinases 2 and 9. J Neurol Sci 2017. [DOI: 10.1016/j.jns.2017.08.2176] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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15
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Kim H, Ovchinnikov D, Deiana D, Unuchek D, Kis A. Suppressing Nucleation in Metal-Organic Chemical Vapor Deposition of MoS 2 Monolayers by Alkali Metal Halides. Nano Lett 2017; 17:5056-5063. [PMID: 28700239 DOI: 10.1021/acs.nanolett.7b02311] [Citation(s) in RCA: 90] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
Toward the large-area deposition of MoS2 layers, we employ metal-organic precursors of Mo and S for a facile and reproducible van der Waals epitaxy on c-plane sapphire. Exposing c-sapphire substrates to alkali metal halide salts such as KI or NaCl together with the Mo precursor prior to the start of the growth process results in increasing the lateral dimensions of single crystalline domains by more than 2 orders of magnitude. The MoS2 grown this way exhibits high crystallinity and optoelectronic quality comparable to single-crystal MoS2 produced by conventional chemical vapor deposition methods. The presence of alkali metal halides suppresses the nucleation and enhances enlargement of domains while resulting in chemically pure MoS2 after transfer. Field-effect measurements in polymer electrolyte-gated devices result in promising electron mobility values close to 100 cm2 V-1 s-1 at cryogenic temperatures.
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Affiliation(s)
- HoKwon Kim
- Electrical Engineering Institute, École Polytechnique Fédérale de Lausanne (EPFL) , CH-1015 Lausanne, Switzerland
- Institute of Materials Science and Engineering, École Polytechnique Fédérale de Lausanne (EPFL) , CH-1015 Lausanne, Switzerland
| | - Dmitry Ovchinnikov
- Electrical Engineering Institute, École Polytechnique Fédérale de Lausanne (EPFL) , CH-1015 Lausanne, Switzerland
- Institute of Materials Science and Engineering, École Polytechnique Fédérale de Lausanne (EPFL) , CH-1015 Lausanne, Switzerland
| | - Davide Deiana
- Interdisciplinary Center for Electron Microscopy (CIME), École Polytechnique Fédérale de Lausanne (EPFL) , CH-1015 Lausanne, Switzerland
| | - Dmitrii Unuchek
- Electrical Engineering Institute, École Polytechnique Fédérale de Lausanne (EPFL) , CH-1015 Lausanne, Switzerland
- Institute of Materials Science and Engineering, École Polytechnique Fédérale de Lausanne (EPFL) , CH-1015 Lausanne, Switzerland
| | - Andras Kis
- Electrical Engineering Institute, École Polytechnique Fédérale de Lausanne (EPFL) , CH-1015 Lausanne, Switzerland
- Institute of Materials Science and Engineering, École Polytechnique Fédérale de Lausanne (EPFL) , CH-1015 Lausanne, Switzerland
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16
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Kovalskii V, Shubin A, Chen Y, Ovchinnikov D, Ruzankin S, Hasegawa J, Zilberberg I, Parmon V. Hidden radical reactivity of the [FeO] 2+ group in the H-abstraction from methane: DFT and CASPT2 supported mechanism by the example of model iron (hydro)oxide species. Chem Phys Lett 2017. [DOI: 10.1016/j.cplett.2017.05.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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17
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Chen MW, Ovchinnikov D, Lazar S, Pizzochero M, Whitwick MB, Surrente A, Baranowski M, Sanchez OL, Gillet P, Plochocka P, Yazyev OV, Kis A. Highly Oriented Atomically Thin Ambipolar MoSe 2 Grown by Molecular Beam Epitaxy. ACS Nano 2017; 11:6355-6361. [PMID: 28530829 PMCID: PMC5492213 DOI: 10.1021/acsnano.7b02726] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/19/2017] [Accepted: 05/22/2017] [Indexed: 05/19/2023]
Abstract
Transition metal dichalcogenides (TMDCs), together with other two-dimensional (2D) materials, have attracted great interest due to the unique optical and electrical properties of atomically thin layers. In order to fulfill their potential, developing large-area growth and understanding the properties of TMDCs have become crucial. Here, we have used molecular beam epitaxy (MBE) to grow atomically thin MoSe2 on GaAs(111)B. No intermediate compounds were detected at the interface of as-grown films. Careful optimization of the growth temperature can result in the growth of highly aligned films with only two possible crystalline orientations due to broken inversion symmetry. As-grown films can be transferred onto insulating substrates, allowing their optical and electrical properties to be probed. By using polymer electrolyte gating, we have achieved ambipolar transport in MBE-grown MoSe2. The temperature-dependent transport characteristics can be explained by the 2D variable-range hopping (2D-VRH) model, indicating that the transport is strongly limited by the disorder in the film.
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Affiliation(s)
- Ming-Wei Chen
- Electrical
Engineering Institute, École Polytechnique
Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
- Institute
of Materials Science and Engineering, École
Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Dmitry Ovchinnikov
- Electrical
Engineering Institute, École Polytechnique
Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
- Institute
of Materials Science and Engineering, École
Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Sorin Lazar
- FEI
Electron Optics, 5600 KA Eindhoven, The Netherlands
| | - Michele Pizzochero
- Institute
of Physics, École Polytechnique Fédérale
de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Michael Brian Whitwick
- Electrical
Engineering Institute, École Polytechnique
Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Alessandro Surrente
- Laboratoire
National
des Champs Magnétiques Intenses CNRS-UGA-UPS-INSA, 143 avenue de Rangueil, 31400 Toulouse, France
| | - Michał Baranowski
- Laboratoire
National
des Champs Magnétiques Intenses CNRS-UGA-UPS-INSA, 143 avenue de Rangueil, 31400 Toulouse, France
- Department
of Experimental Physics, Faculty of Fundamental Problems of Technology, Wrocław University of Science and Technology, Wybrzeze Wyspianskiego 27, 50-370 Wrocław, Poland
| | - Oriol Lopez Sanchez
- Electrical
Engineering Institute, École Polytechnique
Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
- Institute
of Materials Science and Engineering, École
Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Philippe Gillet
- Institute
of Physics, École Polytechnique Fédérale
de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Paulina Plochocka
- Laboratoire
National
des Champs Magnétiques Intenses CNRS-UGA-UPS-INSA, 143 avenue de Rangueil, 31400 Toulouse, France
| | - Oleg V. Yazyev
- Institute
of Physics, École Polytechnique Fédérale
de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Andras Kis
- Electrical
Engineering Institute, École Polytechnique
Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
- Institute
of Materials Science and Engineering, École
Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
- E-mail:
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18
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Sanchez OL, Ovchinnikov D, Misra S, Allain A, Kis A. Valley Polarization by Spin Injection in a Light-Emitting van der Waals Heterojunction. Nano Lett 2016; 16:5792-7. [PMID: 27575518 PMCID: PMC5025824 DOI: 10.1021/acs.nanolett.6b02527] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2016] [Revised: 08/26/2016] [Indexed: 05/20/2023]
Abstract
The band structure of transition metal dichalcogenides (TMDCs) with valence band edges at different locations in the momentum space could be harnessed to build devices that operate relying on the valley degree of freedom. To realize such valleytronic devices, it is necessary to control and manipulate the charge density in these valleys, resulting in valley polarization. While this has been demonstrated using optical excitation, generation of valley polarization in electronic devices without optical excitation remains difficult. Here, we demonstrate spin injection from a ferromagnetic electrode into a heterojunction based on monolayers of WSe2 and MoS2 and lateral transport of spin-polarized holes within the WSe2 layer. The resulting valley polarization leads to circularly polarized light emission that can be tuned using an external magnetic field. This demonstration of spin injection and magnetoelectronic control over valley polarization provides a new opportunity for realizing combined spin and valleytronic devices based on spin-valley locking in semiconducting TMDCs.
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Affiliation(s)
| | | | - Shikhar Misra
- Department of Materials Science and Engineering, Indian Institute of Technology (IIT) , Kanpur 208016 India
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19
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Ovchinnikov D, Gargiulo F, Allain A, Pasquier DJ, Dumcenco D, Ho CH, Yazyev OV, Kis A. Disorder engineering and conductivity dome in ReS2 with electrolyte gating. Nat Commun 2016; 7:12391. [PMID: 27499375 PMCID: PMC4979068 DOI: 10.1038/ncomms12391] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2016] [Accepted: 06/29/2016] [Indexed: 11/09/2022] Open
Abstract
Atomically thin rhenium disulphide (ReS2) is a member of the transition metal dichalcogenide family of materials. This two-dimensional semiconductor is characterized by weak interlayer coupling and a distorted 1T structure, which leads to anisotropy in electrical and optical properties. Here we report on the electrical transport study of mono- and multilayer ReS2 with polymer electrolyte gating. We find that the conductivity of monolayer ReS2 is completely suppressed at high carrier densities, an unusual feature unique to monolayers, making ReS2 the first example of such a material. Using dual-gated devices, we can distinguish the gate-induced doping from the electrostatic disorder induced by the polymer electrolyte itself. Theoretical calculations and a transport model indicate that the observed conductivity suppression can be explained by a combination of a narrow conduction band and Anderson localization due to electrolyte-induced disorder.
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Affiliation(s)
- Dmitry Ovchinnikov
- Electrical Engineering Institute, École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland.,Institute of Materials Science and Engineering, École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Fernando Gargiulo
- Institute of Physics, École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Adrien Allain
- Electrical Engineering Institute, École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland.,Institute of Materials Science and Engineering, École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Diego José Pasquier
- Institute of Physics, École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Dumitru Dumcenco
- Electrical Engineering Institute, École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland.,Institute of Materials Science and Engineering, École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Ching-Hwa Ho
- Graduate Institute of Applied Science and Technology, National Taiwan University of Science and Technology, Taipei 106, Taiwan
| | - Oleg V Yazyev
- Institute of Physics, École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Andras Kis
- Electrical Engineering Institute, École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland.,Institute of Materials Science and Engineering, École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
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20
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Feng J, Graf M, Liu K, Ovchinnikov D, Dumcenco D, Heiranian M, Nandigana V, Aluru NR, Kis A, Radenovic A. Single-layer MoS2 nanopores as nanopower generators. Nature 2016; 536:197-200. [DOI: 10.1038/nature18593] [Citation(s) in RCA: 613] [Impact Index Per Article: 76.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2015] [Accepted: 05/13/2016] [Indexed: 12/23/2022]
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21
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Dumcenco D, Ovchinnikov D, Marinov K, Lazić P, Gibertini M, Marzari N, Sanchez OL, Kung YC, Krasnozhon D, Chen MW, Bertolazzi S, Gillet P, Fontcuberta i Morral A, Radenovic A, Kis A. Large-Area Epitaxial Monolayer MoS2. ACS Nano 2015; 9:4611-20. [PMID: 25843548 PMCID: PMC4415455 DOI: 10.1021/acsnano.5b01281] [Citation(s) in RCA: 317] [Impact Index Per Article: 35.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/27/2015] [Accepted: 03/30/2015] [Indexed: 05/19/2023]
Abstract
Two-dimensional semiconductors such as MoS2 are an emerging material family with wide-ranging potential applications in electronics, optoelectronics, and energy harvesting. Large-area growth methods are needed to open the way to applications. Control over lattice orientation during growth remains a challenge. This is needed to minimize or even avoid the formation of grain boundaries, detrimental to electrical, optical, and mechanical properties of MoS2 and other 2D semiconductors. Here, we report on the growth of high-quality monolayer MoS2 with control over lattice orientation. We show that the monolayer film is composed of coalescing single islands with limited numbers of lattice orientation due to an epitaxial growth mechanism. Optical absorbance spectra acquired over large areas show significant absorbance in the high-energy part of the spectrum, indicating that MoS2 could also be interesting for harvesting this region of the solar spectrum and fabrication of UV-sensitive photodetectors. Even though the interaction between the growth substrate and MoS2 is strong enough to induce lattice alignment via van der Waals interaction, we can easily transfer the grown material and fabricate devices. Local potential mapping along channels in field-effect transistors shows that the single-crystal MoS2 grains in our film are well connected, with interfaces that do not degrade the electrical conductivity. This is also confirmed by the relatively large and length-independent mobility in devices with a channel length reaching 80 μm.
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Affiliation(s)
- Dumitru Dumcenco
- Electrical Engineering Institute, Institute of Materials, Institute of Condensed Matter Physics, and Institute of Bioengineering, Ecole Polytechnique Federale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Dmitry Ovchinnikov
- Electrical Engineering Institute, Institute of Materials, Institute of Condensed Matter Physics, and Institute of Bioengineering, Ecole Polytechnique Federale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Kolyo Marinov
- Electrical Engineering Institute, Institute of Materials, Institute of Condensed Matter Physics, and Institute of Bioengineering, Ecole Polytechnique Federale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Predrag Lazić
- Institute Ruđer Bošković (IRB), HR-10000 Zagreb, Croatia
| | - Marco Gibertini
- Electrical Engineering Institute, Institute of Materials, Institute of Condensed Matter Physics, and Institute of Bioengineering, Ecole Polytechnique Federale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Nicola Marzari
- Electrical Engineering Institute, Institute of Materials, Institute of Condensed Matter Physics, and Institute of Bioengineering, Ecole Polytechnique Federale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Oriol Lopez Sanchez
- Electrical Engineering Institute, Institute of Materials, Institute of Condensed Matter Physics, and Institute of Bioengineering, Ecole Polytechnique Federale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Yen-Cheng Kung
- Electrical Engineering Institute, Institute of Materials, Institute of Condensed Matter Physics, and Institute of Bioengineering, Ecole Polytechnique Federale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Daria Krasnozhon
- Electrical Engineering Institute, Institute of Materials, Institute of Condensed Matter Physics, and Institute of Bioengineering, Ecole Polytechnique Federale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Ming-Wei Chen
- Electrical Engineering Institute, Institute of Materials, Institute of Condensed Matter Physics, and Institute of Bioengineering, Ecole Polytechnique Federale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Simone Bertolazzi
- Electrical Engineering Institute, Institute of Materials, Institute of Condensed Matter Physics, and Institute of Bioengineering, Ecole Polytechnique Federale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Philippe Gillet
- Electrical Engineering Institute, Institute of Materials, Institute of Condensed Matter Physics, and Institute of Bioengineering, Ecole Polytechnique Federale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Anna Fontcuberta i Morral
- Electrical Engineering Institute, Institute of Materials, Institute of Condensed Matter Physics, and Institute of Bioengineering, Ecole Polytechnique Federale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Aleksandra Radenovic
- Electrical Engineering Institute, Institute of Materials, Institute of Condensed Matter Physics, and Institute of Bioengineering, Ecole Polytechnique Federale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Andras Kis
- Electrical Engineering Institute, Institute of Materials, Institute of Condensed Matter Physics, and Institute of Bioengineering, Ecole Polytechnique Federale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
- Address correspondence to
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Arner E, Daub CO, Vitting-Seerup K, Andersson R, Lilje B, Drabløs F, Lennartsson A, Rönnerblad M, Hrydziuszko O, Vitezic M, Freeman TC, Alhendi AMN, Arner P, Axton R, Baillie JK, Beckhouse A, Bodega B, Briggs J, Brombacher F, Davis M, Detmar M, Ehrlund A, Endoh M, Eslami A, Fagiolini M, Fairbairn L, Faulkner GJ, Ferrai C, Fisher ME, Forrester L, Goldowitz D, Guler R, Ha T, Hara M, Herlyn M, Ikawa T, Kai C, Kawamoto H, Khachigian LM, Klinken SP, Kojima S, Koseki H, Klein S, Mejhert N, Miyaguchi K, Mizuno Y, Morimoto M, Morris KJ, Mummery C, Nakachi Y, Ogishima S, Okada-Hatakeyama M, Okazaki Y, Orlando V, Ovchinnikov D, Passier R, Patrikakis M, Pombo A, Qin XY, Roy S, Sato H, Savvi S, Saxena A, Schwegmann A, Sugiyama D, Swoboda R, Tanaka H, Tomoiu A, Winteringham LN, Wolvetang E, Yanagi-Mizuochi C, Yoneda M, Zabierowski S, Zhang P, Abugessaisa I, Bertin N, Diehl AD, Fukuda S, Furuno M, Harshbarger J, Hasegawa A, Hori F, Ishikawa-Kato S, Ishizu Y, Itoh M, Kawashima T, Kojima M, Kondo N, Lizio M, Meehan TF, Mungall CJ, Murata M, Nishiyori-Sueki H, Sahin S, Nagao-Sato S, Severin J, de Hoon MJL, Kawai J, Kasukawa T, Lassmann T, Suzuki H, Kawaji H, Summers KM, Wells C, Hume DA, Forrest ARR, Sandelin A, Carninci P, Hayashizaki Y. Transcribed enhancers lead waves of coordinated transcription in transitioning mammalian cells. Science 2015; 347:1010-4. [PMID: 25678556 PMCID: PMC4681433 DOI: 10.1126/science.1259418] [Citation(s) in RCA: 405] [Impact Index Per Article: 45.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Although it is generally accepted that cellular differentiation requires changes to transcriptional networks, dynamic regulation of promoters and enhancers at specific sets of genes has not been previously studied en masse. Exploiting the fact that active promoters and enhancers are transcribed, we simultaneously measured their activity in 19 human and 14 mouse time courses covering a wide range of cell types and biological stimuli. Enhancer RNAs, then messenger RNAs encoding transcription factors, dominated the earliest responses. Binding sites for key lineage transcription factors were simultaneously overrepresented in enhancers and promoters active in each cellular system. Our data support a highly generalizable model in which enhancer transcription is the earliest event in successive waves of transcriptional change during cellular differentiation or activation.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | - David A. Hume
- Corresponding author. (D.A.H.); (A.R.R.F.); (A.S.); (P.C.); (Y.H.)
| | | | - Albin Sandelin
- Corresponding author. (D.A.H.); (A.R.R.F.); (A.S.); (P.C.); (Y.H.)
| | - Piero Carninci
- Corresponding author. (D.A.H.); (A.R.R.F.); (A.S.); (P.C.); (Y.H.)
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Abstract
We report on the fabrication of field-effect transistors based on single layers and bilayers of the semiconductor WS2 and the investigation of their electronic transport properties. We find that the doping level strongly depends on the device environment and that long in situ annealing drastically improves the contact transparency, allowing four-terminal measurements to be performed and the pristine properties of the material to be recovered. Our devices show n-type behavior with a high room-temperature on/off current ratio of ∼10(6). They show clear metallic behavior at high charge carrier densities and mobilities as high as ∼140 cm(2)/(V s) at low temperatures (above 300 cm(2)/(V s) in the case of bilayers). In the insulating regime, the devices exhibit variable-range hopping, with a localization length of about 2 nm that starts to increase as the Fermi level enters the conduction band. The promising electronic properties of WS2, comparable to those of single-layer MoS2 and WSe2, together with its strong spin-orbit coupling, make it interesting for future applications in electronic, optical, and valleytronic devices.
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Affiliation(s)
- Dmitry Ovchinnikov
- Electrical Engineering Institute, Ecole Polytechnique Federale de Lausanne (EPFL) , CH-1015 Lausanne, Switzerland
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Kao LP, Ovchinnikov D, Wolvetang E. The effect of ethidium bromide and chloramphenicol on mitochondrial biogenesis in primary human fibroblasts. Toxicol Appl Pharmacol 2012; 261:42-9. [DOI: 10.1016/j.taap.2012.03.009] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Abstract
The vertebrate cranial vault, or calvaria, forms during embryonic development from cranial mesenchyme of multiple embryonic origins. Inductive interactions are thought to specify the number and location of the calvarial bones, including interactions between the neuroepithelium and cranial mesenchyme. An important feature of calvarial development is the local inhibition of osteogenic potential which occurs between specific bones and results in the formation of the cranial sutures. These sutures allow for postnatal growth of the skull to accommodate postnatal increase in brain size. The molecular genetic mechanisms responsible for the patterning of individual calvarial bones and for the specification of the number and location of sutures are poorly understood at the molecular genetic level. Here we report on the function and expression pattern of the LIM-homeodomain gene, lmx1b, during calvarial development. Lmx1b is expressed in the neuroepithelium underlying portions of the developing skull and in cranial mesenchyme which contributes to portions of the cranial vault. Lmx1b is essential for proper patterning and morphogenesis of the calvaria since the supraoccipital and interparietal bones of lmx1b mutant mice are either missing or severely reduced. Moreover, lmx1b mutant mice have severely abnormal sutures between the frontal, parietal, and interparietal bones. Our results indicate that lmx1b is required for multiple events in calvarial development and suggest possible genetic interaction with other genes known to regulate skull development and suture formation.
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Affiliation(s)
- H Chen
- Department of Biochemistry and Molecular Biology, UT MD Anderson Cancer Center, Houston 77030, USA
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Chen H, Lun Y, Ovchinnikov D, Kokubo H, Oberg KC, Pepicelli CV, Gan L, Lee B, Johnson RL. Limb and kidney defects in Lmx1b mutant mice suggest an involvement of LMX1B in human nail patella syndrome. Nat Genet 1998; 19:51-5. [PMID: 9590288 DOI: 10.1038/ng0598-51] [Citation(s) in RCA: 336] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Dorsal-ventral limb patterning in vertebrates is thought to be controlled by the LIM-homeodomain protein Lmx1b which is expressed in a spatially and temporally restricted manner along the dorsal-ventral limb axis. Here we describe the phenotype resulting from targeted disruption of Lmx1b. Our results demonstrate that Lmx1b is essential for the specification of dorsal limb fates at both the zeugopodal and autopodal level with prominent phenotypes including an absence of nails and patellae. These features are similar to those present in a dominantly inherited human condition called nail patella syndrome (NPS), which also has renal involvement. Mouse Lmx1b maps to a region syntenic to that of the NPS gene, and kidneys of Lmx1b mutant mice exhibit pathological changes similar to that observed in NPS (refs 5,6). Our results demonstrate an essential function for Lmx1b in mouse limb and kidney development and suggest that NPS might result from mutations in the human LMX1B gene.
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Affiliation(s)
- H Chen
- Department of Biochemistry and Molecular Biology, U.T. M.D. Anderson Cancer Center, Houston, USA
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