Query：
学者姓名：裴家杰
Refining：
Year
Type
Indexed by
Source
Complex
Co-
Language
Clean All
Abstract ：
2D transition metal dichalcogenides (TMDs) have emerged as a novel class of semiconductors with promising applications in optoelectronics, owing to their rich and tunable valley fine structure, known as valleytronics. Strain engineering in TMDs presents opportunities to tailor their valley fine structures and band alignment, which greatly expands the potential to investigate their intrinsic properties and improve device performance, thus opening a new field of straintronics. In this review, recent advances in strain-engineered 2D TMDs are summarized, with a focus on new phenomena and applications enabled by precision tuning of valley physics. The underlying mechanisms and connections are delineated between strain-induced modifications to the valley fine structures based on intravalley, intervalley, and interlayer band alignment in single and heterostructure TMDs. These insights allow targeted strain control strategies to be devised for optimizing optoelectronic characteristics. This review provides perspectives and guidance on the future directions of valley-straintronics and flexible 2D optoelectronics using TMDs, highlighting the substantial promise of valley-strain engineering in TMDs for fundamental valley physics studies as well as practical device applications. Presenting a comprehensive review on recent advancements in strain-engineered 2D transition metal dichalcogenides (TMDs). This review delves into precision tuning of valley physics through strain engineering, elucidating mechanisms and connections between strain-induced modifications and optoelectronic characteristics. It offers insights into future directions of valley-straintronics, underscoring the significant promise of valley-strain engineering in TMDs for fundamental studies and practical applications. image
Keyword ：
2D semiconductors 2D semiconductors straintronics straintronics transition metal dichalcogenides transition metal dichalcogenides valley fine structure valley fine structure valleytronics valleytronics
Cite：
Copy from the list or Export to your reference management。
| GB/T 7714 | Yang, Shichao , Long, Hanyan , Chen, Wenwei et al. Valleytronics Meets Straintronics: Valley Fine Structure Engineering of 2D Transition Metal Dichalcogenides [J]. | ADVANCED OPTICAL MATERIALS , 2024 , 12 (14) . |
| MLA | Yang, Shichao et al. "Valleytronics Meets Straintronics: Valley Fine Structure Engineering of 2D Transition Metal Dichalcogenides" . | ADVANCED OPTICAL MATERIALS 12 . 14 (2024) . |
| APA | Yang, Shichao , Long, Hanyan , Chen, Wenwei , Sa, Baisheng , Guo, Zhiyong , Zheng, Jingying et al. Valleytronics Meets Straintronics: Valley Fine Structure Engineering of 2D Transition Metal Dichalcogenides . | ADVANCED OPTICAL MATERIALS , 2024 , 12 (14) . |
| Export to | NoteExpress RIS BibTex |
Version ：
Abstract ：
van der Waals (vdW) superlattices, comprising different 2D materials aligned alternately by weak interlayer interactions, offer versatile structures for the fabrication of novel semiconductor devices. Despite their potential, the precise control of optoelectronic properties with interlayer interactions remains challenging. Here, we investigate the discrepancies between the SnS/TiS2 superlattice (SnTiS3) and its subsystems by comprehensive characterization and DFT calculations. The disappearance of certain Raman modes suggests that the interactions alter the SnS subsystem structure. Specifically, such structural changes transform the band structure from indirect to direct band gap, causing a strong PL emission (similar to 2.18 eV) in SnTiS3. In addition, the modulation of the optoelectronic properties ultimately leads to the unique phenomenon of thermally activated photoluminescence. This phenomenon is attributed to the inhibition of charge transfer induced by tunable intralayer strains. Our findings extend the understanding of the mechanism of interlayer interactions in van der Waals superlattices and provide insights into the design of high-temperature optoelectronic devices.
Keyword ：
interlayer interactions interlayer interactions photoluminescence photoluminescence SnTiS3 SnTiS3 temperature-dependent temperature-dependent van der Waals heterostructures van der Waals heterostructures
Cite：
Copy from the list or Export to your reference management。
| GB/T 7714 | Huang, Siting , Bai, Jiahui , Long, Hanyan et al. Thermally Activated Photoluminescence Induced by Tunable Interlayer Interactions in Naturally Occurring van der Waals Superlattice SnS/TiS2 [J]. | NANO LETTERS , 2024 , 24 (20) : 6061-6068 . |
| MLA | Huang, Siting et al. "Thermally Activated Photoluminescence Induced by Tunable Interlayer Interactions in Naturally Occurring van der Waals Superlattice SnS/TiS2" . | NANO LETTERS 24 . 20 (2024) : 6061-6068 . |
| APA | Huang, Siting , Bai, Jiahui , Long, Hanyan , Yang, Shichao , Chen, Wenwei , Wang, Qiuyan et al. Thermally Activated Photoluminescence Induced by Tunable Interlayer Interactions in Naturally Occurring van der Waals Superlattice SnS/TiS2 . | NANO LETTERS , 2024 , 24 (20) , 6061-6068 . |
| Export to | NoteExpress RIS BibTex |
Version ：
Abstract ：
Monolayer group VI transition metal dichalcogenides (TMDs) have recently emerged as promising candidates for photon-ic and opto-valleytronic applications. The optoelectronic properties of these atomically-thin semiconducting crystals are strongly governed by the tightly bound electron-hole pairs such as excitons and trions (charged excitons). The anomal-ous spin and valley configurations at the conduction band edges in monolayer WS2 give rise to even more fascinating valley many-body complexes. Here we find that the indirect Q valley in the first Brillouin zone of monolayer WS2 plays a critical role in the formation of a new excitonic state, which has not been well studied. By employing a high-quality h-BN encapsulated WS2 field-effect transistor, we are able to switch the electron concentration within K-Q valleys at conduc-tion band edges. Consequently, a distinct emission feature could be excited at the high electron doping region. Such fea-ture has a competing population with the K valley trion, and experiences nonlinear power-law response and lifetime dy-namics under doping. Our findings open up a new avenue for the study of valley many-body physics and quantum optics in semiconducting 2D materials, as well as provide a promising way of valley manipulation for next-generation entangled photonic devices.
Keyword ：
2D materials 2D materials charged excitons charged excitons indirect Q-valley indirect Q-valley trions trions valleytronics valleytronics WS2 WS2
Cite：
Copy from the list or Export to your reference management。
| GB/T 7714 | Pei, Jiajie , Liu, Xue , del Aguila, Andres Granados et al. Switching of K-Q intervalley trions fine structure and their dynamics in n-doped monolayer WS2 [J]. | OPTO-ELECTRONIC ADVANCES , 2023 , 6 (4) . |
| MLA | Pei, Jiajie et al. "Switching of K-Q intervalley trions fine structure and their dynamics in n-doped monolayer WS2" . | OPTO-ELECTRONIC ADVANCES 6 . 4 (2023) . |
| APA | Pei, Jiajie , Liu, Xue , del Aguila, Andres Granados , Bao, Di , Liu, Sheng , Amara, Mohamed-Raouf et al. Switching of K-Q intervalley trions fine structure and their dynamics in n-doped monolayer WS2 . | OPTO-ELECTRONIC ADVANCES , 2023 , 6 (4) . |
| Export to | NoteExpress RIS BibTex |
Version ：
Abstract ：
Two-dimensional (2D) transition metal chalcogenides (TMDs) are regarded as promising materials for micro-optoelectronic devices and next-generation logic devices due to their novel optoelectronic properties, such as strong excitonic effects, tunable direct bandgap from visible to near-infrared regions, valley pseudospin degree of freedom, and so on. Recently, triggered by the growing demand to optimize the performance of TMDs devices, external field regulation engineering has attracted great attention. The goal of this operation is to exploit the external fields to control exciton dynamics in 2D TMDs, including exciton formation and relaxation, and to finally achieve high-performance 2D TMDs devices. Although the regulation strategies of exciton dynamics in 2D TMDs have been well explored, the underlying mechanisms of different regulation strategies need to be further understood due to the complex many-body interactions in exciton dynamics. Here, we first give a brief summary of the fundamental processes of exciton dynamics in 2D TMDs and then summarize the main field-regulation strategies. Particular emphasis is placed on discussing the underlying mechanisms of how different field-regulation strategies control varied fundamental processes. A deep understanding of field regulation provides direct guidelines for the integrated design of 2D TMDs devices in the future.
Cite：
Copy from the list or Export to your reference management。
| GB/T 7714 | Chen, Wenwei , Zheng, Canghai , Pei, Jiajie et al. External field regulation strategies for exciton dynamics in 2D TMDs [J]. | OPTICAL MATERIALS EXPRESS , 2023 , 13 (4) : 1007-1030 . |
| MLA | Chen, Wenwei et al. "External field regulation strategies for exciton dynamics in 2D TMDs" . | OPTICAL MATERIALS EXPRESS 13 . 4 (2023) : 1007-1030 . |
| APA | Chen, Wenwei , Zheng, Canghai , Pei, Jiajie , Zhan, Hongbing . External field regulation strategies for exciton dynamics in 2D TMDs . | OPTICAL MATERIALS EXPRESS , 2023 , 13 (4) , 1007-1030 . |
| Export to | NoteExpress RIS BibTex |
Version ：
Abstract ：
Triggered by the expanding demands of semiconductor devices, strain engineering of two-dimensional transition metal dichalcogenides (TMDs) has garnered considerable research interest. Through steady-state measurements, strain has been proved in terms of its modulation of electronic energy bands and optoelectronic properties in TMDs. However, the influence of strain on the spin-orbit coupling as well as its related valley excitonic dynamics remains elusive. Here, we demonstrate the effect of strain on the excitonic dynamics of monolayer WS2 via steady-state fluorescence and transient absorption spectroscopy. Combined with theoretical calculations, we found that tensile strain can reduce the spin-splitting value of the conduction band and lead to transitions between different exciton states via spin-flip mechanism. Our findings suggest that the spin-flip process is strain-dependent, provides a reference for application of valleytronic devices, where tensile strain is usually existing during their design and fabrication.
Keyword ：
spin and valley dynamics spin and valley dynamics strain engineering strain engineering transient absorption spectroscopy transient absorption spectroscopy transition metal dichalcogenides transition metal dichalcogenides
Cite：
Copy from the list or Export to your reference management。
| GB/T 7714 | Yang, Shichao , Chen, Wenwei , Sa, Baisheng et al. Strain-Dependent Band Splitting and Spin-Flip Dynamics in Monolayer WS2 [J]. | NANO LETTERS , 2023 , 23 (7) : 3070-3077 . |
| MLA | Yang, Shichao et al. "Strain-Dependent Band Splitting and Spin-Flip Dynamics in Monolayer WS2" . | NANO LETTERS 23 . 7 (2023) : 3070-3077 . |
| APA | Yang, Shichao , Chen, Wenwei , Sa, Baisheng , Guo, Zhiyong , Zheng, Jingying , Pei, Jiajie et al. Strain-Dependent Band Splitting and Spin-Flip Dynamics in Monolayer WS2 . | NANO LETTERS , 2023 , 23 (7) , 3070-3077 . |
| Export to | NoteExpress RIS BibTex |
Version ：
Abstract ：
Low-dimensional bismuth oxychalcogenides have shown promising potential in optoelectronics due to their high stability, photoresponse, and carrier mobility. However, the relevant studies on deep understanding for Bi2O2S is quite limited. Here, comprehensive experimental and computational investigations are conducted in the regulated band structure, nonlinear optical (NLO) characteristics, and carrier dynamics of Bi2O2S nanosheets via defect engineering, taking O vacancy (OV) and substitutional Se doping as examples. As the OV continuously increased to approximate to 35%, the optical bandgaps progressively narrow from approximate to 1.21 to approximate to 0.81 eV and NLO wavelengths are extended to near-infrared regions with enhanced saturable absorption. Simultaneously, the relaxation processes are effectively accelerated from tens of picoseconds to several picoseconds, as the generated defect energy levels can serve as both additional absorption cross-sections and fast relaxation channels supported by theoretical calculations. Furthermore, substitutional Se doping in Bi2O2S nanosheets also modulate their optical properties with the similar trends. As a proof-of-concept, passively mode-locked pulsed lasers in the approximate to 1.0 mu m based on the defect-rich samples (approximate to 35% OV and approximate to 50% Se-doping) exhibit excellent performance. This work deepens the insight of defect functions on optical properties of Bi2O2S nanosheets and provides new avenues for designing advanced photonic devices based on low-dimensional bismuth oxychalcogenides.
Keyword ：
bismuth oxysulfide bismuth oxysulfide nonlinear optics nonlinear optics oxygen vacancies oxygen vacancies Se doping Se doping ultrafast carrier dynamics ultrafast carrier dynamics
Cite：
Copy from the list or Export to your reference management。
| GB/T 7714 | Dong, Junhao , Zhang, Lesong , Lau, Kuenyao et al. Tailoring Broadband Nonlinear Optical Characteristics and Ultrafast Photocarrier Dynamics of Bi2O2S Nanosheets by Defect Engineering [J]. | SMALL , 2023 , 20 (24) . |
| MLA | Dong, Junhao et al. "Tailoring Broadband Nonlinear Optical Characteristics and Ultrafast Photocarrier Dynamics of Bi2O2S Nanosheets by Defect Engineering" . | SMALL 20 . 24 (2023) . |
| APA | Dong, Junhao , Zhang, Lesong , Lau, Kuenyao , Shu, Yu , Wang, Shijin , Fu, Zhuang et al. Tailoring Broadband Nonlinear Optical Characteristics and Ultrafast Photocarrier Dynamics of Bi2O2S Nanosheets by Defect Engineering . | SMALL , 2023 , 20 (24) . |
| Export to | NoteExpress RIS BibTex |
Version ：
Abstract ：
This chapter presents an overview of the concept of “valleys” in semiconductor physics, which refers to local minima in the energy bands of certain semiconductors. These energy bands are crucial for determining the electronic and optical properties of the material. Specifically, some semiconductor crystals, like transition metal dichalcogenides (TMDs), exhibit multiple valleys with varying energies, resulting in distinct effective masses and pseudospins for charge carriers. The focus of the chapter is on valley excitonic states that arise from strong interactions between electrons and holes in different valleys. These interactions, along with additional carriers in the electronic band structure, lead to the formation of valley many-body complexes, including intervalley trions, biexcitons, and charged biexcitons. The formation processes, energy valley configurations, fluorescence and absorption peak positions, and changes in polarization characteristics of various valley excitonic states in TMDs under external fields are explored and summarized in this chapter. These complexes possess diverse optical and electronic properties, making them promising for applications in optoelectronics, quantum information processing, and valleytronics. Additionally, recently discovered moiré exciton states and their relationship with energy valleys in momentum space are discussed. However, research on polarization characteristics in these states is in its early stages, necessitating further exploration. © 2023
Keyword ：
Excitonic states Excitonic states Many-body complexes Many-body complexes Optoelectronic properties Optoelectronic properties Transition metal dichalcogenides (TMDs) Transition metal dichalcogenides (TMDs) Valleys Valleys
Cite：
Copy from the list or Export to your reference management。
| GB/T 7714 | Pei, J. , Xu, R. . Valley excitons and their many-body complexes [未知]. |
| MLA | Pei, J. et al. "Valley excitons and their many-body complexes" [未知]. |
| APA | Pei, J. , Xu, R. . Valley excitons and their many-body complexes [未知]. |
| Export to | NoteExpress RIS BibTex |
Version ：
Abstract ：
A series of two-dimensional polyimide covalent organic frameworks (2D COF) based on core-substituted naphthalene diimides (cNDIs) were designed and synthesized with the characteristic of tunable bandgap without global structural changes. Cyclic voltammetry (CV) and DFT calculations indicated that COFcNDI-OEt and COF(cNDI-SEt )possess higher HOMO/LUMO levels and narrower bandgaps than COFNDI-H. Further investigation indicated that the COF bandgaps are not only related to the electron-donating substituents but also varied with respect to the interlayer distances. Moreover, the femtosecond transient absorption (TA) spectra manifested that the electron donor substituents are beneficial to the charge delocalization in the pi-columnar unit, resulting in a longer lifetime of charge recombination, which is one of the pivotal prerequisites for high-performance solar cells and photocatalysis.
Keyword ：
carrier dynamics carrier dynamics covalent organic frameworks covalent organic frameworks naphthalenediimides naphthalenediimides polyimide polyimide substituent effect substituent effect
Cite：
Copy from the list or Export to your reference management。
| GB/T 7714 | Luo, Yafang , Chang, Zhen , Pei, Jiajie et al. Design, Synthesis, and Ultrafast Carrier Dynamics of Core-Substituted Naphthalene Diimide-Based Covalent Organic Frameworks [J]. | NANO LETTERS , 2023 , 23 (20) : 9266-9271 . |
| MLA | Luo, Yafang et al. "Design, Synthesis, and Ultrafast Carrier Dynamics of Core-Substituted Naphthalene Diimide-Based Covalent Organic Frameworks" . | NANO LETTERS 23 . 20 (2023) : 9266-9271 . |
| APA | Luo, Yafang , Chang, Zhen , Pei, Jiajie , Guo, Zhiyong , Zhan, Hongbing . Design, Synthesis, and Ultrafast Carrier Dynamics of Core-Substituted Naphthalene Diimide-Based Covalent Organic Frameworks . | NANO LETTERS , 2023 , 23 (20) , 9266-9271 . |
| Export to | NoteExpress RIS BibTex |
Version ：
Abstract ：
Monolayer transition metal dichalcogenides (mTMDs) possess a direct band gap and strong PL emission that is highly sensitive to doping level and interfaces, laying the foundation for investigating the contact between mTMD and metal via PL spectroscopy. Currently, electrical methods have been utilized to measure the contact resistance (R-C), but they are complicated, time-consuming, high-cost and suffer from inevitable chemical disorders and Fermi level pinning. In addition, previously reported contact resistances comprise both Schottky barrier and tunnel barrier components. Here, we report a simple, rapid and low-cost method to study the tunnel barrier dominated contact resistance of mTMD based junctions through PL spectroscopy. These junctions are free from chemical disorders and Fermi level pinning. Excluding the Schottky barrier component, solely tunnel barrier dominated contact resistances of 1 L MoSe2/Au and 1 L MoSe2/graphene junctions were estimated to be 147.8 omega mu m and 54.9 omega mu m, respectively. Density functional theory (DFT) simulations revealed that the larger R-C of the former was possibly due to the existence of intrinsic effective potential difference (phi(barrier)) between mTMD and metal. Both junctions exhibit an increasing tendency of R-C as temperature decreases, which is probably attributed to the thermal expansion coefficient (TEC) mismatch-triggered interlayer spacing (d) increase and temperature-induced doping. Remarkably, a significant change of R-C was observed in 1 L MoSe2/Au junctions, which is possibly ascribed to the changes of their orbital overlaps. Our results open new avenues for exploring fundamental metal-semiconductor contact principles and constructing high-performance devices.
Cite：
Copy from the list or Export to your reference management。
| GB/T 7714 | Zhang, Linglong , Tang, Yilin , Yan, Han et al. Direct observation of contact resistivity for monolayer TMD based junctions via PL spectroscopy [J]. | NANOSCALE , 2022 , 14 (23) : 8260-8270 . |
| MLA | Zhang, Linglong et al. "Direct observation of contact resistivity for monolayer TMD based junctions via PL spectroscopy" . | NANOSCALE 14 . 23 (2022) : 8260-8270 . |
| APA | Zhang, Linglong , Tang, Yilin , Yan, Han , Yildirim, Tanju , Yang, Shunshun , Song, Haizeng et al. Direct observation of contact resistivity for monolayer TMD based junctions via PL spectroscopy . | NANOSCALE , 2022 , 14 (23) , 8260-8270 . |
| Export to | NoteExpress RIS BibTex |
Version ：
Abstract ：
Developing novel optical materials with large and ultrafast nonlinear optical (NLO) response is significant for photonics and optoelectronics. Cuprates as the representative one-dimensional (1D) strongly correlated material show promising NLO properties, but relevant research is quite rare. Here, using Ca2CuO3 nanosheets as the prototype, we systematically explored the NLO performance and ultrafast carrier dynamics of these cuprate nanosheets prepared by a ball-milling process. The obtained Ca2CuO3 nanosheets exhibited convertible NLO behavior from saturable absorption (SA) to reverse saturable absorption (RSA) with strong absorption coefficient, induced by increasing wavelengths and duration of excitation pulse. In addition, we revealed their ultrashort relaxation time in (sub-)picosecond scale for photogenerated carriers, mainly owing to the midgap state-assisted recombination by emitting multiple phonons and spinons. Furthermore, the similar NLO feature also investigated in isostructural Sr2CuO3 and Ba2CuO3 nanosheets further indicated the excellent NLO performance of 1D strongly correlated cuprates. This work opens up a new avenue for future photonics with 1D strongly correlated materials as the novel platforms.
Keyword ：
Ca2CuO3 Ca2CuO3 Cuprate Cuprate Nonlinear optics Nonlinear optics Strongly correlated material Strongly correlated material Ultrafast carrier dynamics Ultrafast carrier dynamics
Cite：
Copy from the list or Export to your reference management。
| GB/T 7714 | Song, Miaomiao , Huang, Yongfeng , Hao, Ruixian et al. Nonlinear optical absorption characteristics and ultrafast carrier dynamics of one-dimensional strongly correlated cuprate nanosheets [J]. | APPLIED SURFACE SCIENCE , 2022 , 593 . |
| MLA | Song, Miaomiao et al. "Nonlinear optical absorption characteristics and ultrafast carrier dynamics of one-dimensional strongly correlated cuprate nanosheets" . | APPLIED SURFACE SCIENCE 593 (2022) . |
| APA | Song, Miaomiao , Huang, Yongfeng , Hao, Ruixian , Dong, Junhao , Wu, Wensheng , Fu, Zhuang et al. Nonlinear optical absorption characteristics and ultrafast carrier dynamics of one-dimensional strongly correlated cuprate nanosheets . | APPLIED SURFACE SCIENCE , 2022 , 593 . |
| Export to | NoteExpress RIS BibTex |
Version ：
Export
| Results： |
Selected to |
| Format： |
