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Perea-Causin R, Brem S, Buchner F, Lu Y, Watanabe K, Taniguchi T, Lupton JM, Lin KQ, Malic E. Electrically tunable layer-hybridized trions in doped WSe 2 bilayers. Nat Commun 2024; 15:6713. [PMID: 39112462 PMCID: PMC11306803 DOI: 10.1038/s41467-024-50834-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2024] [Accepted: 07/16/2024] [Indexed: 08/10/2024] Open
Abstract
Doped van der Waals heterostructures host layer-hybridized trions, i.e. charged excitons with layer-delocalized constituents holding promise for highly controllable optoelectronics. Combining a microscopic theory with photoluminescence (PL) experiments, we demonstrate the electrical tunability of the trion energy landscape in naturally stacked WSe2 bilayers. We show that an out-of-plane electric field modifies the energetic ordering of the lowest lying trion states, which consist of layer-hybridized Λ -point electrons and layer-localized K-point holes. At small fields, intralayer-like trions yield distinct PL signatures in opposite doping regimes characterized by weak Stark shifts in both cases. Above a doping-asymmetric critical field, interlayer-like species are energetically favored and produce PL peaks with a pronounced Stark red-shift and a counter-intuitively large intensity arising from efficient phonon-assisted recombination. Our work presents an important step forward in the microscopic understanding of layer-hybridized trions in van der Waals heterostructures and paves the way towards optoelectronic applications based on electrically controllable atomically-thin semiconductors.
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Affiliation(s)
- Raul Perea-Causin
- Department of Physics, Chalmers University of Technology, Gothenburg, Sweden.
- Department of Physics, Stockholm University, Stockholm, Sweden.
| | - Samuel Brem
- Department of Physics, Philipps-Universität Marburg, Marburg, Germany
| | - Fabian Buchner
- Department of Physics, University of Regensburg, Regensburg, Germany
| | - Yao Lu
- State Key Laboratory of Physical Chemistry of Solid Surfaces, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, China
| | - Kenji Watanabe
- Research Center for Electronic and Optical Materials, National Institute for Materials Science, Tsukuba, Japan
| | - Takashi Taniguchi
- Research Center for Materials Nanoarchitectonics, National Institute for Materials Science, Tsukuba, Japan
| | - John M Lupton
- Department of Physics, University of Regensburg, Regensburg, Germany
| | - Kai-Qiang Lin
- Department of Physics, University of Regensburg, Regensburg, Germany.
- State Key Laboratory of Physical Chemistry of Solid Surfaces, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, China.
| | - Ermin Malic
- Department of Physics, Philipps-Universität Marburg, Marburg, Germany.
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2
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Jing Y, Liang K, Muir NS, Zhou H, Li Z, Palasz JM, Sorbie J, Wang C, Cushing SK, Kubiak CP, Sofer Z, Li S, Xiong W. Ultrafast Formation of Charge Transfer Trions at Molecular-Functionalized 2D MoS 2 Interfaces. Angew Chem Int Ed Engl 2024; 63:e202405123. [PMID: 38714495 DOI: 10.1002/anie.202405123] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2024] [Revised: 05/03/2024] [Accepted: 05/07/2024] [Indexed: 05/10/2024]
Abstract
In this work, we investigate trion dynamics occurring at the heterojunction between organometallic molecules and a monolayer transition metal dichalcogenide (TMD) with transient electronic sum frequency generation (tr-ESFG) spectroscopy. By pumping at 2.4 eV with laser pulses, we have observed an ultrafast hole transfer, succeeded by the emergence of charge-transfer trions. This observation is facilitated by the cancellation of ground state bleach and stimulated emission signals due to their opposite phases, making tr-ESFG especially sensitive to the trion formation dynamics. The presence of charge-transfer trion at molecular functionalized TMD monolayers suggests the potential for engineering the local electronic structures and dynamics of specific locations on TMDs and offers a potential for transferring unique electronic attributes of TMD to the molecular layers.
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Affiliation(s)
- Yuancheng Jing
- Department of Chemistry and Biochemistry, University of California, San Diego, 9500 Gilman Drive, MC 0358, La Jolla, California, 92093-0358, United States
| | - Kangkai Liang
- Material Science and Engineering Program, University of California, San Diego, 9500 Gilman Drive, MC 0418, La Jolla, California, 92093-0418, United States
| | - Nicole S Muir
- Department of Chemistry and Biochemistry, University of California, San Diego, 9500 Gilman Drive, MC 0358, La Jolla, California, 92093-0358, United States
| | - Hao Zhou
- Material Science and Engineering Program, University of California, San Diego, 9500 Gilman Drive, MC 0418, La Jolla, California, 92093-0418, United States
| | - Zhehao Li
- Material Science and Engineering Program, University of California, San Diego, 9500 Gilman Drive, MC 0418, La Jolla, California, 92093-0418, United States
| | - Joseph M Palasz
- Department of Chemistry and Biochemistry, University of California, San Diego, 9500 Gilman Drive, MC 0358, La Jolla, California, 92093-0358, United States
| | - Jonathan Sorbie
- Department of Chemistry and Biochemistry, University of California, San Diego, 9500 Gilman Drive, MC 0358, La Jolla, California, 92093-0358, United States
| | - Chenglai Wang
- Department of Chemistry and Biochemistry, University of California, San Diego, 9500 Gilman Drive, MC 0358, La Jolla, California, 92093-0358, United States
| | - Scott K Cushing
- Division of Chemistry and Chemical Engineering, California Institute of Technology, 1200 E California Blvd, MC 127-72, Pasadena, California, 91125, United States
| | - Clifford P Kubiak
- Department of Chemistry and Biochemistry, University of California, San Diego, 9500 Gilman Drive, MC 0358, La Jolla, California, 92093-0358, United States
| | - Zdeněk Sofer
- Department of Inorganic Chemistry, University of Chemistry and Technology, Prague, Technická 5, 166 28, Prague 6, Czech Republic
| | - Shaowei Li
- Department of Chemistry and Biochemistry, University of California, San Diego, 9500 Gilman Drive, MC 0358, La Jolla, California, 92093-0358, United States
- Material Science and Engineering Program, University of California, San Diego, 9500 Gilman Drive, MC 0418, La Jolla, California, 92093-0418, United States
| | - Wei Xiong
- Department of Chemistry and Biochemistry, University of California, San Diego, 9500 Gilman Drive, MC 0358, La Jolla, California, 92093-0358, United States
- Material Science and Engineering Program, University of California, San Diego, 9500 Gilman Drive, MC 0418, La Jolla, California, 92093-0418, United States
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3
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Lin KQ, Faria Junior PE, Hübner R, Ziegler JD, Bauer JM, Buchner F, Florian M, Hofmann F, Watanabe K, Taniguchi T, Fabian J, Steinhoff A, Chernikov A, Bange S, Lupton JM. Ultraviolet interlayer excitons in bilayer WSe 2. NATURE NANOTECHNOLOGY 2024; 19:196-201. [PMID: 38049597 DOI: 10.1038/s41565-023-01544-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2023] [Accepted: 10/15/2023] [Indexed: 12/06/2023]
Abstract
Interlayer excitons in van der Waals heterostructures are fascinating for applications like exciton condensation, excitonic devices and moiré-induced quantum emitters. The study of these charge-transfer states has almost exclusively focused on band edges, limiting the spectral region to the near-infrared regime. Here we explore the above-gap analogues of interlayer excitons in bilayer WSe2 and identify both neutral and charged species emitting in the ultraviolet. Even though the transitions occur far above the band edge, the states remain metastable, exhibiting linewidths as narrow as 1.8 meV. These interlayer high-lying excitations have switchable dipole orientations and hence show prominent Stark splitting. The positive and negative interlayer high-lying trions exhibit significant binding energies of 20-30 meV, allowing for a broad tunability of transitions via electric fields and electrostatic doping. The Stark splitting of these trions serves as a highly accurate, built-in sensor for measuring interlayer electric field strengths, which are exceedingly difficult to quantify otherwise. Such excitonic complexes are further sensitive to the interlayer twist angle and offer opportunities to explore emergent moiré physics under electrical control. Our findings more than double the accessible energy range for applications based on interlayer excitons.
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Affiliation(s)
- Kai-Qiang Lin
- State Key Laboratory of Physical Chemistry of Solid Surfaces, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, China.
- Department of Physics, University of Regensburg, Regensburg, Germany.
| | | | - Ruven Hübner
- Institute for Theoretical Physics and Bremen Center for Computational Materials Science, University of Bremen, Bremen, Germany
| | - Jonas D Ziegler
- Institute of Applied Physics and Würzburg-Dresden Cluster of Excellence ct.qmat, Technische Universität Dresden, Dresden, Germany
| | - Jonas M Bauer
- Department of Physics, University of Regensburg, Regensburg, Germany
| | - Fabian Buchner
- Department of Physics, University of Regensburg, Regensburg, Germany
| | - Matthias Florian
- Department of Electrical Engineering and Computer Science, University of Michigan, Ann Arbor, MI, USA
| | - Felix Hofmann
- Department of Physics, University of Regensburg, Regensburg, Germany
| | - Kenji Watanabe
- Center for Functional Materials, National Institute for Materials Science, Tsukuba, Japan
| | - Takashi Taniguchi
- International Center for Materials Nanoarchitectonics, National Institute for Materials Science, Tsukuba, Japan
| | - Jaroslav Fabian
- Department of Physics, University of Regensburg, Regensburg, Germany
| | - Alexander Steinhoff
- Institute for Theoretical Physics and Bremen Center for Computational Materials Science, University of Bremen, Bremen, Germany
| | - Alexey Chernikov
- Institute of Applied Physics and Würzburg-Dresden Cluster of Excellence ct.qmat, Technische Universität Dresden, Dresden, Germany
| | - Sebastian Bange
- Department of Physics, University of Regensburg, Regensburg, Germany
| | - John M Lupton
- Department of Physics, University of Regensburg, Regensburg, Germany
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4
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Zhang S, Sun D, Sun J, Ma K, Wei Z, Park JY, Coffey AH, Zhu C, Dou L, Huang L. Unraveling the Effect of Stacking Configurations on Charge Transfer in WS 2 and Organic Semiconductor Heterojunctions. PRECISION CHEMISTRY 2023; 1:443-451. [PMID: 37771515 PMCID: PMC10526440 DOI: 10.1021/prechem.3c00057] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/30/2023] [Revised: 06/06/2023] [Accepted: 06/08/2023] [Indexed: 09/30/2023]
Abstract
Photoinduced interfacial charge transfer plays a critical role in energy conversion involving van der Waals (vdW) heterostructures constructed of inorganic nanostructures and organic materials. However, the effect of molecular stacking configurations on charge transfer dynamics is less understood. In this study, we demonstrated the tunability of interfacial charge separation in a type-II heterojunction between monolayer (ML) WS2 and an organic semiconducting molecule [2-(3″',4'-dimethyl-[2,2':5',2':5″,2″'-quaterthiophen]-5-yl)ethan-1-ammonium halide (4Tm)] by rational design of relative stacking configurations. The assembly between ML-WS2 and the 4Tm molecule forms a face-to-face stacking when 4Tm molecules are in a self-aggregation state. In contrast, a face-to-edge stacking is observed when 4Tm molecule is incorporated into a 2D organic-inorganic hybrid perovskite lattice. The face-to-face stacking was proved to be more favorable for hole transfer from WS2 to 4Tm and led to interlayer excitons (IEs) emission. Transient absorption measurements show that the hole transfer occurs on a time scale of 150 fs. On the other hand, the face-to-edge stacking resulted in much slower hole transfer without formation of IEs. This inefficient hole transfer occurs on a similar time scale as A exciton recombination in WS2, leading to the formation of negative trions. These investigations offer important fundamental insights into the charge transfer processes at organic-inorganic interfaces.
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Affiliation(s)
- Shuchen Zhang
- Davidson
School of Chemical Engineering, Purdue University, West Lafayette, Indiana 47907, United States
| | - Dewei Sun
- Department
of Chemistry, Purdue University, West Lafayette, Indiana 47907, United States
| | - Jiaonan Sun
- Davidson
School of Chemical Engineering, Purdue University, West Lafayette, Indiana 47907, United States
| | - Ke Ma
- Davidson
School of Chemical Engineering, Purdue University, West Lafayette, Indiana 47907, United States
| | - Zitang Wei
- Davidson
School of Chemical Engineering, Purdue University, West Lafayette, Indiana 47907, United States
| | - Jee Yung Park
- Davidson
School of Chemical Engineering, Purdue University, West Lafayette, Indiana 47907, United States
| | - Aidan H. Coffey
- Advanced
Light Source, Lawrence Berkeley National
Laboratory, Berkeley, California 94720, United States
| | - Chenhui Zhu
- Advanced
Light Source, Lawrence Berkeley National
Laboratory, Berkeley, California 94720, United States
| | - Letian Dou
- Davidson
School of Chemical Engineering, Purdue University, West Lafayette, Indiana 47907, United States
- Birck
Nanotechnology Center, Purdue University, West Lafayette, Indiana 47907, United States
| | - Libai Huang
- Department
of Chemistry, Purdue University, West Lafayette, Indiana 47907, United States
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5
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Zhang M, Zhang J. Highly Selective NH 3 Sensor Based on MoS 2/WS 2 Heterojunction. NANOMATERIALS (BASEL, SWITZERLAND) 2023; 13:1835. [PMID: 37368265 DOI: 10.3390/nano13121835] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/24/2023] [Revised: 05/26/2023] [Accepted: 06/05/2023] [Indexed: 06/28/2023]
Abstract
In this paper, the heterostructure of MoS2/WS2 was prepared by a hydrothermal method; the n-n heterostructure was demonstrated using TEM combined with Mott-Schottky analysis. The valence and conduction band positions were further identified by the XPS valence band spectra. The NH3-sensing properties were assessed at room temperature by changing the mass ratio of the MoS2 and WS2 components. The 50 wt%-MoS2/WS2 sample exhibited the best performance, with a peak response of 23643% to NH3 at a concentration of 500 ppm, a minimum detection limit of 20 ppm, and a fast recovery time of 2.6 s. Furthermore, the composites-based sensors demonstrated an excellent humidity immune property with less than one order of magnitude in the humidity range of 11-95% RH, revealing the practical application value of these sensors. These results suggest that the MoS2/WS2 heterojunction is an intriguing candidate for fabricating NH3 sensors.
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Affiliation(s)
- Min Zhang
- Xinjiang Key Laboratory of Solid State Physics and Devices, Xinjiang University, Urumqi 830046, China
- School of Physics Science and Technology, Xinjiang University, Urumqi 830046, China
| | - Jinzhu Zhang
- Xinjiang Key Laboratory of Solid State Physics and Devices, Xinjiang University, Urumqi 830046, China
- School of Physics Science and Technology, Xinjiang University, Urumqi 830046, China
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6
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Koo Y, Lee H, Ivanova T, Kefayati A, Perebeinos V, Khestanova E, Kravtsov V, Park KD. Tunable interlayer excitons and switchable interlayer trions via dynamic near-field cavity. LIGHT, SCIENCE & APPLICATIONS 2023; 12:59. [PMID: 36864035 PMCID: PMC9981773 DOI: 10.1038/s41377-023-01087-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Revised: 01/07/2023] [Accepted: 02/01/2023] [Indexed: 06/18/2023]
Abstract
Emerging photo-induced excitonic processes in transition metal dichalcogenide (TMD) heterobilayers, e.g., interplay of intra- and inter-layer excitons and conversion of excitons to trions, allow new opportunities for ultrathin hybrid photonic devices. However, with the associated large degree of spatial heterogeneity, understanding and controlling their complex competing interactions in TMD heterobilayers at the nanoscale remains a challenge. Here, we present an all-round dynamic control of interlayer-excitons and -trions in a WSe2/Mo0.5 W0.5 Se2 heterobilayer using multifunctional tip-enhanced photoluminescence (TEPL) spectroscopy with <20 nm spatial resolution. Specifically, we demonstrate the bandgap tunable interlayer excitons and the dynamic interconversion between interlayer-trions and -excitons, through the combinational tip-induced engineering of GPa-scale pressure and plasmonic hot electron injection, with simultaneous spectroscopic TEPL measurements. This unique nano-opto-electro-mechanical control approach provides new strategies for developing versatile nano-excitonic/trionic devices using TMD heterobilayers.
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Affiliation(s)
- Yeonjeong Koo
- Department of Physics, Pohang University of Science and Technology (POSTECH), Pohang, 37673, Republic of Korea
| | - Hyeongwoo Lee
- Department of Physics, Pohang University of Science and Technology (POSTECH), Pohang, 37673, Republic of Korea
| | - Tatiana Ivanova
- School of Physics and Engineering, ITMO University, Saint Petersburg, 197101, Russia
| | - Ali Kefayati
- Department of Electrical Engineering, University at Buffalo, New York, NY, 14260, USA
| | - Vasili Perebeinos
- Department of Electrical Engineering, University at Buffalo, New York, NY, 14260, USA
| | - Ekaterina Khestanova
- School of Physics and Engineering, ITMO University, Saint Petersburg, 197101, Russia
| | - Vasily Kravtsov
- School of Physics and Engineering, ITMO University, Saint Petersburg, 197101, Russia.
| | - Kyoung-Duck Park
- Department of Physics, Pohang University of Science and Technology (POSTECH), Pohang, 37673, Republic of Korea.
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7
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Zhang L, Zhou F, Zhang X, Yang S, Wen B, Yan H, Yildirim T, Song X, Yang Q, Tian M, Wan N, Song H, Pei J, Qin S, Zhu J, Wageh S, Al-Hartomy OA, Al-Sehemi AG, Shen H, Liu Y, Zhang H. Discovery of Type II Interlayer Trions. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2023; 35:e2206212. [PMID: 36373507 DOI: 10.1002/adma.202206212] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/08/2022] [Revised: 10/25/2022] [Indexed: 06/16/2023]
Abstract
In terms of interlayer trions, electronic excitations in van der Waals heterostructures (vdWHs) can be classified into Type I (i.e., two identical charges in the same layer) and Type II (i.e., two identical charges in the different layers). Type I interlayer trions are investigated theoretically and experimentally. By contrast, Type II interlayer trions remain elusive in vdWHs, due to inadequate free charges, unsuitable band alignment, reduced Coulomb interactions, poor interface quality, etc. Here, the first observation of Type II interlayer trions is reported by exploring band alignments and choosing an atomically thin organic-inorganic system-monolayer WSe2 /bilayer pentacene heterostructure (1L + 2L HS). Both positive and negative Type II interlayer trions are electrically tuned and observed via PL spectroscopy. In particular, Type II interlayer trions exhibit in-plane anisotropic emission, possibly caused by their unique spatial structure and anisotropic charge interactions, which is highly correlated with the transition dipole moment of pentacene. The results pave the way to develop excitonic devices and all-optical circuits using atomically thin organic-inorganic bilayers.
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Affiliation(s)
- Linglong Zhang
- College of Physics, Nanjing University of Aeronautics and Astronautics, Key Laboratory of Aerospace Information Materials and Physics (NUAA), MIIT, Nanjing, 211106, China
| | - Fei Zhou
- State Key Laboratory for Environment-friendly Energy Materials, School of Materials and Chemistry, Southwest University of Science and Technology, Mianyang, 621010, China
| | - Xiaowei Zhang
- Department of Electrical Engineering and Computer Science, Ningbo University, Ningbo, 315211, China
| | - Shunshun Yang
- College of Physics, Nanjing University of Aeronautics and Astronautics, Key Laboratory of Aerospace Information Materials and Physics (NUAA), MIIT, Nanjing, 211106, China
| | - Bo Wen
- Institute of Nanosurface Science and Engineering, Guangdong Provincial Key Laboratory of Micro/Nano Optomechatronics Engineering, Shenzhen University, Shenzhen, 518060, China
| | - Han Yan
- Department of Materials Science and Metallurgy, University of Cambridge, Cambridge, CB3 0FS, UK
| | - Tanju Yildirim
- Center for Functional Sensor & Actuator (CFSN), National Institute for Materials Science (NIMS), Tsukuba, Ibaraki, 305-0044, Japan
| | - Xiaoying Song
- College of Optoelectronic Engineering, Chongqing University of Posts and Telecommunications, Chongqing, 400065, China
| | - Qi Yang
- Intstitue of Microscale Optoelectronics, College of Physics and Optoelectronic Engineering, Shenzhen University, Shenzhen, 518060, China
| | - Ming Tian
- SEU-FEI Nano Pico Center, Key Laboratory of MEMS of Ministry of Education, School of Electronics Science and Engineering, Southeast University, Nanjing, 210096, China
| | - Neng Wan
- SEU-FEI Nano Pico Center, Key Laboratory of MEMS of Ministry of Education, School of Electronics Science and Engineering, Southeast University, Nanjing, 210096, China
| | - Hucheng Song
- Center of Energy Storage Materials & Technology, College of Engineering and Applied Sciences, National Laboratory of Solid State Microstructures/Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, China
| | - Jiajie Pei
- College of Materials Science and Engineering, Fuzhou University, Fuzhou, Fujian, 350108, China
| | - Shuchao Qin
- Key Laboratory of Optical Communication Science and Technology of Shandong Province, School of Physical Science and Information Engineering, Liaocheng University, Liaocheng, 252059, China
| | - Jiaqi Zhu
- Intstitue of Microscale Optoelectronics, College of Physics and Optoelectronic Engineering, Shenzhen University, Shenzhen, 518060, China
| | - S Wageh
- Department of Physics, Faculty of Science, King Abdulaziz University, Jeddah, 21589, Saudi Arabia
| | - Omar A Al-Hartomy
- Department of Physics, Faculty of Science, King Abdulaziz University, Jeddah, 21589, Saudi Arabia
| | - Abdullah G Al-Sehemi
- Research Center for Advanced Materials Science (RCAMS), King Khalid University, P.O. Box 9004, Abha, 61413, Saudi Arabia
| | | | - Youwen Liu
- College of Physics, Nanjing University of Aeronautics and Astronautics, Key Laboratory of Aerospace Information Materials and Physics (NUAA), MIIT, Nanjing, 211106, China
| | - Han Zhang
- Intstitue of Microscale Optoelectronics, College of Physics and Optoelectronic Engineering, Shenzhen University, Shenzhen, 518060, China
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8
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Bieniek M, Sadecka K, Szulakowska L, Hawrylak P. Theory of Excitons in Atomically Thin Semiconductors: Tight-Binding Approach. NANOMATERIALS (BASEL, SWITZERLAND) 2022; 12:1582. [PMID: 35564291 PMCID: PMC9104105 DOI: 10.3390/nano12091582] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/26/2022] [Revised: 04/24/2022] [Accepted: 04/26/2022] [Indexed: 02/01/2023]
Abstract
Atomically thin semiconductors from the transition metal dichalcogenide family are materials in which the optical response is dominated by strongly bound excitonic complexes. Here, we present a theory of excitons in two-dimensional semiconductors using a tight-binding model of the electronic structure. In the first part, we review extensive literature on 2D van der Waals materials, with particular focus on their optical response from both experimental and theoretical points of view. In the second part, we discuss our ab initio calculations of the electronic structure of MoS2, representative of a wide class of materials, and review our minimal tight-binding model, which reproduces low-energy physics around the Fermi level and, at the same time, allows for the understanding of their electronic structure. Next, we describe how electron-hole pair excitations from the mean-field-level ground state are constructed. The electron-electron interactions mix the electron-hole pair excitations, resulting in excitonic wave functions and energies obtained by solving the Bethe-Salpeter equation. This is enabled by the efficient computation of the Coulomb matrix elements optimized for two-dimensional crystals. Next, we discuss non-local screening in various geometries usually used in experiments. We conclude with a discussion of the fine structure and excited excitonic spectra. In particular, we discuss the effect of band nesting on the exciton fine structure; Coulomb interactions; and the topology of the wave functions, screening and dielectric environment. Finally, we follow by adding another layer and discuss excitons in heterostructures built from two-dimensional semiconductors.
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Affiliation(s)
- Maciej Bieniek
- Department of Physics, University of Ottawa, Ottawa, ON K1N 6N5, Canada; (K.S.); (L.S.); (P.H.)
- Department of Theoretical Physics, Wrocław University of Science and Technology, Wybrzeże Wyspiańskiego 27, 50-370 Wrocław, Poland
- Institut für Theoretische Physik und Astrophysik, Universität Würzburg, 97074 Würzburg, Germany
| | - Katarzyna Sadecka
- Department of Physics, University of Ottawa, Ottawa, ON K1N 6N5, Canada; (K.S.); (L.S.); (P.H.)
- Department of Theoretical Physics, Wrocław University of Science and Technology, Wybrzeże Wyspiańskiego 27, 50-370 Wrocław, Poland
| | - Ludmiła Szulakowska
- Department of Physics, University of Ottawa, Ottawa, ON K1N 6N5, Canada; (K.S.); (L.S.); (P.H.)
| | - Paweł Hawrylak
- Department of Physics, University of Ottawa, Ottawa, ON K1N 6N5, Canada; (K.S.); (L.S.); (P.H.)
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9
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Liu H, Yu S, Wang Y, Huang B, Dai Y, Wei W. Excited-State Properties of CuInP 2S 6 Monolayer as Photocatalyst for Water Splitting. J Phys Chem Lett 2022; 13:1972-1978. [PMID: 35188392 DOI: 10.1021/acs.jpclett.2c00105] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
In recent years, two-dimensional (2D) materials of ferroelectricity have been illustrated to have great potential in solar energy conversion processes such as photocatalytic water splitting, although the optical properties of such materials are rarely discussed. In combination with the first-principles calculations, many-body Green's function method was used to obtain the excited-state properties of the representative CuInP2S6 to unravel the ingredients affecting the photocatalytic behavior. In particular, quasiparticle (QP) band gap correction and bound exciton binding energy are 1.25/1.38 and 0.93/0.87 eV for paraelectric/ferroelectric CuInP2S6, respectively. In addition to facilitating the charge carrier recombination, here we emphasize that the large exciton binding energy reduces the reduction potential of the photoexcited electrons. In bilayer structures, the improved photocatalytic performance should be ascribed to the type-II band alignment and large band edge offsets (0.44 and 0.33 eV for CuInP2S6), rather than the increased light absorption due to the reduced band gap.
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Affiliation(s)
- Hongling Liu
- School of Physics, State Key Laboratory of Crystal Materials, Shandong University, Jinan 250100, China
| | - Shiqiang Yu
- School of Physics, State Key Laboratory of Crystal Materials, Shandong University, Jinan 250100, China
| | - Yuanyuan Wang
- School of Physics, State Key Laboratory of Crystal Materials, Shandong University, Jinan 250100, China
| | - Baibiao Huang
- School of Physics, State Key Laboratory of Crystal Materials, Shandong University, Jinan 250100, China
| | - Ying Dai
- School of Physics, State Key Laboratory of Crystal Materials, Shandong University, Jinan 250100, China
| | - Wei Wei
- School of Physics, State Key Laboratory of Crystal Materials, Shandong University, Jinan 250100, China
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10
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Behera RK, Mishra L, Panigrahi A, Sahoo PK, Sarangi MK. Tunable Conductance of MoS 2 and WS 2 Quantum Dots by Electron Transfer with Redox-Active Quinone. ACS APPLIED MATERIALS & INTERFACES 2022; 14:5750-5761. [PMID: 35049294 DOI: 10.1021/acsami.1c18092] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Due to their uniqueness in tunable photophysics, transition metal dichalcogenide (TMD) based quantum dots (QDs) have emerged as the next-generation quantum materials for technology-based semiconductor applications. This demands frontline research on the rational synthesis of the TMD QDs with controlled shape, size, nature of charge migration at the interface, and their easy integration in optoelectronic devices. In this article, with a controlled solution-processed synthesis of MoS2 and WS2 QDs, we demonstrate the disparity in their structural, optical, and electrical characteristics in bulk and confinement. With a series of steady-state and time-resolved spectroscopic measurements in different media, we explore the uncommon photophysics of MoS2 and WS2 QDs such as excitation-dependent photoluminescence and assess their excited state charge transfer kinetics with a redox-active biomolecule, menadione (MQ). In comparison to the homogeneous aqueous medium, photoinduced charge transfer between the QDs and MQ becomes more plausible in encapsulated cetyltrimethylammonium bromide (CTAB) micelles. Current sensing atomic force microscopy (CS-AFM) measurements at a single molecular level reveal that the facilitated charge transfer of QDs with MQ strongly correlates with an enhancement in their charge transport behavior. An increase in charge transport further depends on the density of states of the QDs directing a change in Schottky emission to Fowler-Nordheim (FN) type of tunneling across the metal-QD-metal junction. The selective response of the TMD QDs while in proximity to external molecules can be used to design advanced optoelectronic devices and applications involving rectifiers and tunnel diodes for future quantum technology.
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Affiliation(s)
- Ranjan Kumar Behera
- Department of Physics, Indian Institute of Technology Patna, Bihta, Kanpa Road, Patna, Bihar 801106, India
| | - Leepsa Mishra
- Department of Physics, Indian Institute of Technology Patna, Bihta, Kanpa Road, Patna, Bihar 801106, India
| | - Aradhana Panigrahi
- Department of Physics, Indian Institute of Technology Patna, Bihta, Kanpa Road, Patna, Bihar 801106, India
| | - Prasana Kumar Sahoo
- Materials Science Centre, Indian Institute of Technology Kharagpur, Kharagpur, West Bengal 721302, India
| | - Manas Kumar Sarangi
- Department of Physics, Indian Institute of Technology Patna, Bihta, Kanpa Road, Patna, Bihar 801106, India
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11
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Amsterdam SH, Marks TJ, Hersam MC. Leveraging Molecular Properties to Tailor Mixed-Dimensional Heterostructures beyond Energy Level Alignment. J Phys Chem Lett 2021; 12:4543-4557. [PMID: 33970639 DOI: 10.1021/acs.jpclett.1c00799] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
The surface sensitivity and lack of dielectric screening in two-dimensional (2D) materials provide numerous intriguing opportunities to tailor their properties using adsorbed π-electron organic molecules. These organic-2D mixed-dimensional heterojunctions are often considered solely in terms of their energy level alignment, i.e., the relative energies of the frontier molecular orbitals versus the 2D material conduction and valence band edges. While this simple model is frequently adequate to describe doping and photoinduced charge transfer, the tools of molecular chemistry enable additional manipulation of properties in organic-2D heterojunctions that are not accessible in other solid-state systems. Fully exploiting these possibilities requires consideration of the details of the organic adlayer beyond its energy level alignment, including hybridization and electrostatics, molecular orientation and thin-film morphology, nonfrontier orbitals and defects, excitonic states, spin, and chirality. This Perspective explores how these relatively overlooked molecular properties offer unique opportunities for tuning optical and electronic characteristics, thereby guiding the rational design of organic-2D mixed-dimensional heterojunctions with emergent properties.
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Affiliation(s)
- Samuel H Amsterdam
- Department of Chemistry and the Materials Research Center, Northwestern University, Evanston, Illinois 60208, United States
| | - Tobin J Marks
- Department of Chemistry and the Materials Research Center, Northwestern University, Evanston, Illinois 60208, United States
- Department of Materials Science and Engineering and the Materials Research Center, Northwestern University, Evanston, Illinois 60208, United States
- Department of Electrical and Computer Engineering, Northwestern University, Evanston, Illinois 60208, United States
| | - Mark C Hersam
- Department of Chemistry and the Materials Research Center, Northwestern University, Evanston, Illinois 60208, United States
- Department of Materials Science and Engineering and the Materials Research Center, Northwestern University, Evanston, Illinois 60208, United States
- Applied Physics Program, Northwestern University, Evanston, Illinois 60208, United States
- Department of Electrical and Computer Engineering, Northwestern University, Evanston, Illinois 60208, United States
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12
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Maity N, Srivastava P, Mishra H, Shinde R, Singh AK. Anisotropic Interlayer Exciton in GeSe/SnS van der Waals Heterostructure. J Phys Chem Lett 2021; 12:1765-1771. [PMID: 33570941 DOI: 10.1021/acs.jpclett.0c03469] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Stacking two or more two-dimensional materials to form a heterostructure is becoming the most effective way to generate new functionalities for specific applications. Herein, using GW and Bethe-Salpeter equation simulations, we demonstrate the generation of linearly polarized, anisotropic intra- and interlayer excitonic bound states in the transition metal monochalcogenide (TMC) GeSe/SnS van der Waals heterostructure. The puckered structure of TMC results in the directional anisotropy in band structure and in the excitonic bound state. Upon the application of compressive/tensile biaxial strain dramatic variation (∓3%) in excitonic energies, the indirect-to-direct semiconductor transition and the red/blue shift of the optical absorption spectrum are observed. The variations in excitonic energies and optical band gap have been attributed to the change in effective dielectric constant and band dispersion upon the application of biaxial strain. The generation and control over the interlayer excitonic energies can find applications in optoelectronics and optical quantum computers and as a gain medium in lasers.
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Affiliation(s)
- Nikhilesh Maity
- Materials Research Centre, Indian Institute of Science, Bangalore 560012, India
| | - Pooja Srivastava
- Amity School of Applied Sciences, Amity University Uttar Pradesh, Lucknow, Uttar Pradesh 226010, India
| | - Himani Mishra
- Materials Research Centre, Indian Institute of Science, Bangalore 560012, India
| | - Ravindra Shinde
- Materials Research Centre, Indian Institute of Science, Bangalore 560012, India
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13
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Zhu X, He J, Zhang R, Cong C, Zheng Y, Zhang H, Zhang S, Chen L. Effects of dielectric screening on the excitonic and critical points properties of WS 2/MoS 2 heterostructures. NANOSCALE 2020; 12:23732-23739. [PMID: 33231235 DOI: 10.1039/d0nr04591h] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Vertical van der Waals heterostructures have aroused great attention for their promising application in next-generation nanoelectronic and optoelectronic devices. The dielectric screening effect plays a key role in the properties of two-dimensional (2D) heterostructures. Here, we studied the dielectric screening effects on the excitonic properties and critical points (CPs) of the WS2/MoS2 heterostructure using spectroscopic ellipsometry (SE). Owing to the type-II band alignment of the WS2/MoS2 heterostructure, charged carriers spatially separated and created an interlayer exciton, and the transition energy and binding energy have been accurately found to be 1.58 ± 0.050 eV and 431.39 ± 127.818 meV by SE, respectively. We found that stacking the WS2/MoS2 vertical heterostructure increases the effective dielectric screening compared with the monolayer counterparts. The increased effective dielectric screening in the WS2/MoS2 heterostructure weakens the long-range Coulomb force between electrons and holes. Consequently, the quasi-particle band gap and the exciton binding energies are reduced, and because of the orbital overlap, more CPs are produced in the WS2/MoS2 heterostructure in the high photon energy range. Our results not only shed light on the interpretation of recent first-principles studies, but also provide important physical support for improving the performance of heterostructure-based optoelectronic devices with tunable functionalities.
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Affiliation(s)
- Xudan Zhu
- Key Laboratory of Micro and Nano Photonic Structures, Ministry of Education, Shanghai Engineering Research Center of Ultra-Precision Optical Manufacturing, School of Information Science and Engineering, Fudan University, Shanghai 200433, China.
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14
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Deilmann T, Rohlfing M, Wurstbauer U. Light-matter interaction in van der Waals hetero-structures. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2020; 32:333002. [PMID: 32244237 DOI: 10.1088/1361-648x/ab8661] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/14/2020] [Accepted: 04/03/2020] [Indexed: 06/11/2023]
Abstract
Even if individual two-dimensional materials own various interesting and unexpected properties, the stacking of such layers leads to van der Waals solids which unite the characteristics of two dimensions with novel features originating from the interlayer interactions. In this topical review, we cover fabrication and characterization of van der Waals hetero-structures with a focus on hetero-bilayers made of monolayers of semiconducting transition metal dichalcogenides. Experimental and theoretical techniques to investigate those hetero-bilayers are introduced. Most recent findings focusing on different transition metal dichalcogenides hetero-structures are presented and possible optical transitions between different valleys, appearance of moiré patterns and signatures of moiré excitons are discussed. The fascinating and fast growing research on van der Waals hetero-bilayers provide promising insights required for their application as emerging quantum-nano materials.
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Affiliation(s)
- Thorsten Deilmann
- Institut für Festkörertheorie, Westfälische Wilhelms-Universität Münster, Wilhelm-Klemm-Str.10, 48149 Münster, Germany
| | - Michael Rohlfing
- Institut für Festkörertheorie, Westfälische Wilhelms-Universität Münster, Wilhelm-Klemm-Str.10, 48149 Münster, Germany
| | - Ursula Wurstbauer
- Institute of Physics, Westfälische Wilhelms-Universität Münster, Wilhelm-Klemm-Str.10, 48149 Münster, Germany
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15
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Interlayer excitons in van der Waals heterostructures: Binding energy, Stark shift, and field-induced dissociation. Sci Rep 2020; 10:5537. [PMID: 32218493 PMCID: PMC7099073 DOI: 10.1038/s41598-020-62431-y] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2020] [Accepted: 03/12/2020] [Indexed: 11/17/2022] Open
Abstract
Photoexcited intralayer excitons in van der Waals heterostructures (vdWHs) with type-II band alignment have been observed to tunnel into interlayer excitons on ultrafast timescales. Such interlayer excitons have sufficiently long lifetimes that inducing dissociation with external in-plane electric fields becomes an attractive option of improving efficiency of photocurrent devices. In the present paper, we calculate interlayer exciton binding energies, Stark shifts, and dissociation rates for six different transition metal dichalcogenide (TMD) vdWHs using a numerical procedure based on exterior complex scaling (ECS). We utilize an analytical bilayer Keldysh potential describing the interaction between the electron-hole pair, and validate its accuracy by comparing to the full multilayer Poisson equation. Based on this model, we obtain an analytical weak-field expression for the exciton dissociation rate. The heterostructures analysed are MoS2/MoSe2, MoS2/WS2, MoS2/WSe2, MoSe2/WSe2, WS2/MoSe2, and WS2/WSe2 in various dielectric environments. For weak electric fields, we find that WS2/WSe2 supports the fastest dissociation rates among the six structures. We, furthermore, observe that exciton dissociation rates in vdWHs are significantly larger than in their monolayer counterparts.
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16
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Calman EV, Fowler-Gerace LH, Choksy DJ, Butov LV, Nikonov DE, Young IA, Hu S, Mishchenko A, Geim AK. Indirect Excitons and Trions in MoSe 2/WSe 2 van der Waals Heterostructures. NANO LETTERS 2020; 20:1869-1875. [PMID: 32069058 DOI: 10.1021/acs.nanolett.9b05086] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
Indirect excitons (IX) in semiconductor heterostructures are bosons, which can cool below the temperature of quantum degeneracy and can be effectively controlled by voltage and light. IX quantum Bose gases and IX devices were explored in GaAs heterostructures where an IX range of existence is limited to low temperatures due to low IX binding energies. IXs in van der Waals transition-metal dichalcogenide (TMD) heterostructures are characterized by large binding energies giving the opportunity for exploring excitonic quantum gases and for creating excitonic devices at high temperatures. TMD heterostructures also offer a new platform for studying single-exciton phenomena and few-particle complexes. In this work, we present studies of IXs in MoSe2/WSe2 heterostructures and report on two IX luminescence lines whose energy splitting and temperature dependence identify them as neutral and charged IXs. The experimentally found binding energy of the indirect charged excitons, that is, indirect trions, is close to the calculated binding energy of 28 meV for negative indirect trions in TMD heterostructures [Deilmann, T.; Thygesen, K. S. Nano Lett. 2018, 18, 1460]. We also report on the realization of IXs with a luminescence line width reaching 4 meV at low temperatures. An enhancement of IX luminescence intensity and the narrow line width are observed in localized spots.
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Affiliation(s)
- E V Calman
- Department of Physics, University of California at San Diego, La Jolla, California 92093, United States
| | - L H Fowler-Gerace
- Department of Physics, University of California at San Diego, La Jolla, California 92093, United States
| | - D J Choksy
- Department of Physics, University of California at San Diego, La Jolla, California 92093, United States
| | - L V Butov
- Department of Physics, University of California at San Diego, La Jolla, California 92093, United States
| | - D E Nikonov
- Components Research, Intel Corporation, Hillsboro, Oregon 97124 United States
| | - I A Young
- Components Research, Intel Corporation, Hillsboro, Oregon 97124 United States
| | - S Hu
- School of Physics and Astronomy, University of Manchester, Oxford Road, Manchester M13 9PL, United Kingdom
| | - A Mishchenko
- School of Physics and Astronomy, University of Manchester, Oxford Road, Manchester M13 9PL, United Kingdom
| | - A K Geim
- School of Physics and Astronomy, University of Manchester, Oxford Road, Manchester M13 9PL, United Kingdom
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17
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Brem S, Zipfel J, Selig M, Raja A, Waldecker L, Ziegler JD, Taniguchi T, Watanabe K, Chernikov A, Malic E. Intrinsic lifetime of higher excitonic states in tungsten diselenide monolayers. NANOSCALE 2019; 11:12381-12387. [PMID: 31215947 DOI: 10.1039/c9nr04211c] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The reduced dielectric screening in atomically thin transition metal dichalcogenides allows to study the hydrogen-like series of higher exciton states in optical spectra even at room temperature. The width of excitonic peaks provides information about the radiative decay and phonon-assisted scattering channels limiting the lifetime of these quasi-particles. While linewidth studies so far have been limited to the exciton ground state, encapsulation with hBN has recently enabled quantitative measurements of the broadening of excited exciton resonances. Here, we present a joint experiment-theory study combining microscopic calculations with spectroscopic measurements on the intrinsic linewidth and lifetime of higher exciton states in hBN-encapsulated WSe2 monolayers. Surprisingly, despite the increased number of scattering channels, we find both in theory and experiment that the linewidth of higher excitonic states is similar or even smaller compared to the ground state. Our microscopic calculations ascribe this behavior to a reduced exciton-phonon scattering efficiency for higher excitons due to spatially extended orbital functions.
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Affiliation(s)
- Samuel Brem
- Chalmers University of Technology, Department of Physics, 41296 Gothenburg, Sweden.
| | - Jonas Zipfel
- University of Regensburg, Department of Physics, 93053 Regensburg, Germany
| | - Malte Selig
- Technical University Berlin, Institute of Theoretical Physics, 10623 Berlin, Germany
| | - Archana Raja
- Kavli Energy NanoScience Institute, University of California Berkeley, Berkeley, USA
| | - Lutz Waldecker
- Stanford University, 348 Via Pueblo Mall, Stanford, California 94305, USA
| | - Jonas D Ziegler
- University of Regensburg, Department of Physics, 93053 Regensburg, Germany
| | - Takashi Taniguchi
- National Institute for Materials Science, Tsukuba, Ibaraki 305-004, Japan
| | - Kenji Watanabe
- National Institute for Materials Science, Tsukuba, Ibaraki 305-004, Japan
| | - Alexey Chernikov
- University of Regensburg, Department of Physics, 93053 Regensburg, Germany
| | - Ermin Malic
- Chalmers University of Technology, Department of Physics, 41296 Gothenburg, Sweden.
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18
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Yang SH, Yao YT, Xu Y, Lin CY, Chang YM, Suen YW, Sun H, Lien CH, Li W, Lin YF. Atomically thin van der Waals tunnel field-effect transistors and its potential for applications. NANOTECHNOLOGY 2019; 30:105201. [PMID: 30530943 DOI: 10.1088/1361-6528/aaf765] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Power dissipation is a crucial problem as the packing density of transistors increases in modern integrated circuits. Tunnel field-effect transistors (TFETs), which have high energy filtering provided by band-to-band tunneling (BTBT), have been proposed as an alternative electronics architecture to decrease the energy loss in bias operation and to achieve steep switching at room temperature. Very recently, the BTBT behavior has been demonstrated in van der Waals heterostructures by using unintentionally doped semiconductors. The reason of the BTBT formation is attributed to a significant band bending near the heterointerface, resulting in carrier accumulations. In this work, to investigate charge transport in type-III transistors, we adopted the same band-bending concept to fabricate van der Waals BP/MoS2 heterostructures. Through analyzing the temperature dependence of their electrical properties, we carefully ruled out the contribution of metal-semiconductor contact resistances and improved our understanding of carrier injection in 2D type-III transistors. The BP/MoS2 heterostructures showed both negative differential resistance and 1/f 2 current fluctuations, strongly demonstrating the BTBT operation. Finally, we also designed a TFET based on this heterostructure with an ionic liquid gate, and this TFET demonstrated an subthreshold slope can successfully surmount the thermal limit of 60 mV/decade. This work improves our understanding of charge transport in such layered heterostructures and helps to improve the energy efficiency of next-generation nanoscale electronics.
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Affiliation(s)
- Shih-Hsien Yang
- Institute of Electronics Engineering, National Tsing Hua University, Hsinchu 30013, Taiwan
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Liu Y, Zhang S, He J, Wang ZM, Liu Z. Recent Progress in the Fabrication, Properties, and Devices of Heterostructures Based on 2D Materials. NANO-MICRO LETTERS 2019; 11:13. [PMID: 34137973 PMCID: PMC7770868 DOI: 10.1007/s40820-019-0245-5] [Citation(s) in RCA: 68] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2018] [Accepted: 01/28/2019] [Indexed: 05/03/2023]
Abstract
With a large number of researches being conducted on two-dimensional (2D) materials, their unique properties in optics, electrics, mechanics, and magnetics have attracted increasing attention. Accordingly, the idea of combining distinct functional 2D materials into heterostructures naturally emerged that provides unprecedented platforms for exploring new physics that are not accessible in a single 2D material or 3D heterostructures. Along with the rapid development of controllable, scalable, and programmed synthesis techniques of high-quality 2D heterostructures, various heterostructure devices with extraordinary performance have been designed and fabricated, including tunneling transistors, photodetectors, and spintronic devices. In this review, we present a summary of the latest progresses in fabrications, properties, and applications of different types of 2D heterostructures, followed by the discussions on present challenges and perspectives of further investigations.
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Affiliation(s)
- Yanping Liu
- School of Physics and Electronics, Hunan Key Laboratory for Super-Microstructure and Ultrafast Process, Central South University, 932 South Lushan Road, Changsha, 410083, Hunan, People's Republic of China.
| | - Siyu Zhang
- School of Physics and Electronics, Hunan Key Laboratory for Super-Microstructure and Ultrafast Process, Central South University, 932 South Lushan Road, Changsha, 410083, Hunan, People's Republic of China
| | - Jun He
- School of Physics and Electronics, Hunan Key Laboratory for Super-Microstructure and Ultrafast Process, Central South University, 932 South Lushan Road, Changsha, 410083, Hunan, People's Republic of China
| | - Zhiming M Wang
- State Key Laboratory of Electronic Thin Films and Integrated Devices, University of Electronic Science and Technology of China, Chengdu, 610054, People's Republic of China.
| | - Zongwen Liu
- School of Chemical and Biomolecular Engineering, The University of Sydney, Sydney, NSW, 2006, Australia.
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Wang Z, Jingjing Q, Wang X, Zhang Z, Chen Y, Huang X, Huang W. Two-dimensional light-emitting materials: preparation, properties and applications. Chem Soc Rev 2018; 47:6128-6174. [DOI: 10.1039/c8cs00332g] [Citation(s) in RCA: 132] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
We review the recent development in two-dimensional (2D) light-emitting materials and describe their preparation methods, optical/optoelectronic properties and applications.
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Affiliation(s)
- Zhiwei Wang
- Institute of Advanced Materials (IAM)
- Nanjing Tech University (NanjingTech)
- Nanjing 211816
- P. R. China
| | - Qiu Jingjing
- Institute of Advanced Materials (IAM)
- Nanjing Tech University (NanjingTech)
- Nanjing 211816
- P. R. China
| | - Xiaoshan Wang
- Institute of Advanced Materials (IAM)
- Nanjing Tech University (NanjingTech)
- Nanjing 211816
- P. R. China
| | - Zhipeng Zhang
- Institute of Advanced Materials (IAM)
- Nanjing Tech University (NanjingTech)
- Nanjing 211816
- P. R. China
| | - Yonghua Chen
- Institute of Advanced Materials (IAM)
- Nanjing Tech University (NanjingTech)
- Nanjing 211816
- P. R. China
| | - Xiao Huang
- Institute of Advanced Materials (IAM)
- Nanjing Tech University (NanjingTech)
- Nanjing 211816
- P. R. China
| | - Wei Huang
- Institute of Advanced Materials (IAM)
- Nanjing Tech University (NanjingTech)
- Nanjing 211816
- P. R. China
- Shaanxi Institute of Flexible Electronics (SIFE)
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