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Shi M, Lv Y, Wu G, Cho J, Abid M, Hung KM, Coileáin CÓ, Chang CR, Wu HC. Band Alignment Transition and Enhanced Performance in Vertical SnS 2/MoS 2 van der Waals Photodetectors. ACS Appl Mater Interfaces 2024; 16:22622-22631. [PMID: 38625091 DOI: 10.1021/acsami.4c00781] [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: 04/17/2024]
Abstract
The strong light-matter interaction and naturally passivated surfaces of van der Waals materials make heterojunctions of such materials ideal candidates for high-performance photodetectors. In this study, we fabricated SnS2/MoS2 van der Waals heterojunctions and investigated their photoelectric properties. Using an applied gate voltage, we can effectively alter the band arrangement and achieve a transition in type II and type I junctions. It is found that the SnS2/MoS2 van der Waals heterostructures are type II heterojunctions when the gate voltage is above -25 V. Below this gate voltage, the heterojunctions become type I. Photoelectric measurements under various wavelengths of incident light reveal enhanced sensitivity in the ultraviolet region and a broadband sensing range from 400 to 800 nm. Moreover, due to the transition from type II to type I band alignment, the measured photocurrent saturates at a specific gate voltage, and this value depends crucially on the bias voltage and light wavelength, providing a potential avenue for designing compact spectrometers.
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Affiliation(s)
- Mingyu Shi
- School of Physics, Beijing Institute of Technology, Beijing 100081, P. R. China
| | - Yanhui Lv
- School of Physics, Beijing Institute of Technology, Beijing 100081, P. R. China
| | - Gang Wu
- School of Physics, Beijing Institute of Technology, Beijing 100081, P. R. China
| | - Jiung Cho
- Western Seoul Center, Korea Basic Science Institute, Seoul 03579, Republic of Korea
- Department of Materials Science and Engineering, Hongik University, Sejong 30016, Republic of Korea
| | - Mohamed Abid
- School of Physics, Beijing Institute of Technology, Beijing 100081, P. R. China
| | - Kuan-Ming Hung
- Department of Electronics Engineering, National Kaohsiung University of Science and Technology, Kaohsiung 807, Taiwan, ROC
| | - Cormac Ó Coileáin
- Institute of Physics, EIT 2, Faculty of Electrical Engineering and Information Technology, University of the Bundeswehr Munich, Neubiberg 85577, Germany
| | - Ching-Ray Chang
- Quantum Information Center, Chung Yuan Christian University, Taoyuan 32023, Taiwan, ROC
- Department of Physics, National Taiwan University, Taipei 106, Taiwan, ROC
| | - Han-Chun Wu
- School of Physics, Beijing Institute of Technology, Beijing 100081, P. R. China
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2
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Wu HC, Xu HS, Xie LC, Jin L. Edge State, Band Topology, and Time Boundary Effect in the Fine-Grained Categorization of Chern Insulators. Phys Rev Lett 2024; 132:083801. [PMID: 38457698 DOI: 10.1103/physrevlett.132.083801] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/24/2023] [Accepted: 01/10/2024] [Indexed: 03/10/2024]
Abstract
We predict novel topological phases with broken time-reversal symmetry supporting the coexistence of opposite chiral edge states, which are fundamentally different from the photonic spin-Hall, valley-Hall, and higher-order topological phases. We find a fine-grained categorization of Chern insulators, their band topologies characterized by identical Chern numbers are completely different. Furthermore, we prove that different topologies cause zeros in their Bloch wave function overlaps, which imprint the band gap closing and appear at the degenerate points of topological phase transition. The Bloch wave function overlaps predict the reflection and refraction at a topological time boundary, and the overlap zeros ensure the existence of vanishing revival amplitude at critical times even though different topologies before and after the time boundary have identical Chern numbers. Our findings create new opportunities for topological metamaterials, uncover the topological feature hidden in the time boundary effect as a probe of topology, and open a venue for the exploration of the rich physics originating from the long-range couplings.
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Affiliation(s)
- H C Wu
- School of Physics, Nankai University, Tianjin 300071, China
- School of Physics, Zhengzhou University, Zhengzhou 450001, China
| | - H S Xu
- School of Physics, Nankai University, Tianjin 300071, China
| | - L C Xie
- School of Physics, Nankai University, Tianjin 300071, China
| | - L Jin
- School of Physics, Nankai University, Tianjin 300071, China
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3
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Cao Z, Zhao Y, Wu G, Cho J, Abid M, Choi M, Ó Coileáin C, Hung KM, Chang CR, Wu HC. Enhanced NO 2 Sensitivity of Vertically Stacked van der Waals Heterostructure Gas Sensor and Its Remarkable Electric and Mechanical Tunability. ACS Appl Mater Interfaces 2024; 16:9495-9505. [PMID: 38334441 DOI: 10.1021/acsami.3c17194] [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: 02/10/2024]
Abstract
Nanodevices based on van der Waals heterostructures have been predicted, and shown, to have unprecedented operational principles and functionalities that hold promise for highly sensitive and selective gas sensors with rapid response times and minimal power consumption. In this study, we fabricated gas sensors based on vertical MoS2/WS2 van der Waals heterostructures and investigated their gas sensing capabilities. Compared with individual MoS2 or WS2 gas sensors, the MoS2/WS2 van der Waals heterostructure gas sensors are shown to have enhanced sensitivity, faster response times, rapid recovery, and a notable selectivity, especially toward NO2. In combination with a theoretical model, we show that it is important to take into account created trapped states (flat bands) induced by the adsorption of gas molecules, which capture charges and alter the inherent built-in potential of van der Waals heterostructure gas sensors. Additionally, we note that the performance of these MoS2/WS2 heterostructure gas sensors could be further enhanced using electrical gating and mechanical strain. Our findings highlight the importance of understanding the effects of altered built-in potentials arising from gas molecule adsorption induced flat bands, thus offering a way to enhance the gas sensing performance of van der Waals heterostructure gas sensors.
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Affiliation(s)
- Ze Cao
- School of Physics, Beijing Institute of Technology, Beijing 100081, P. R. China
| | - Yue Zhao
- School of Physics, Beijing Institute of Technology, Beijing 100081, P. R. China
| | - Gang Wu
- School of Physics, Beijing Institute of Technology, Beijing 100081, P. R. China
| | - Jiung Cho
- Western Seoul Center, Korea Basic Science Institute, Seoul 03579, Republic of Korea
- Department of Advanced Materials Engineering, Chung-Ang University, 4726, Seodong-daero, Daedeok-myeon, Anseong-si, Gyeonggi-do 17546, Republic of Korea
| | - Mohamed Abid
- School of Physics, Beijing Institute of Technology, Beijing 100081, P. R. China
| | - Miri Choi
- Chuncheon Center, Korea Basic Science Institute, Chuncheon 24341, Republic of Korea
| | - Cormac Ó Coileáin
- Institute of Physics, Faculty of Electrical Engineering and Information Technology, University of the Bundeswehr Munich, Neubiberg 85577, Germany
| | - Kuan-Ming Hung
- Department of Electronics Engineering, National Kaohsiung University of Science and Technology, Kaohsiung 807, Taiwan, ROC
| | - Ching-Ray Chang
- Quantum information center, Chung Yuan Christian University, Taoyuan 32023, Taiwan, ROC
- Department of Physics, National Taiwan University, Taipei 106, Taiwan, ROC
| | - Han-Chun Wu
- School of Physics, Beijing Institute of Technology, Beijing 100081, P. R. China
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4
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Wu G, Abid M, Zerara M, Cho J, Choi M, Ó Coileáin C, Hung KM, Chang CR, Shvets IV, Wu HC. Miniaturized spectrometer with intrinsic long-term image memory. Nat Commun 2024; 15:676. [PMID: 38263315 PMCID: PMC10805890 DOI: 10.1038/s41467-024-44884-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2023] [Accepted: 01/09/2024] [Indexed: 01/25/2024] Open
Abstract
Miniaturized spectrometers have great potential for use in portable optoelectronics and wearable sensors. However, current strategies for miniaturization rely on von Neumann architectures, which separate the spectral sensing, storage, and processing modules spatially, resulting in high energy consumption and limited processing speeds due to the storage-wall problem. Here, we present a miniaturized spectrometer that utilizes a single SnS2/ReSe2 van der Waals heterostructure, providing photodetection, spectrum reconstruction, spectral imaging, long-term image memory, and signal processing capabilities. Interface trap states are found to induce a gate-tunable and wavelength-dependent photogating effect and a non-volatile optoelectronic memory effect. Our approach achieves a footprint of 19 μm, a bandwidth from 400 to 800 nm, a spectral resolution of 5 nm, and a > 104 s long-term image memory. Our single-detector computational spectrometer represents a path beyond von Neumann architectures.
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Affiliation(s)
- Gang Wu
- School of Physics, Beijing Institute of Technology, Beijing, 100081, P. R. China
| | - Mohamed Abid
- School of Physics, Beijing Institute of Technology, Beijing, 100081, P. R. China
| | | | - Jiung Cho
- Western Seoul Cente, Korea Basic Science Institute, Seoul, 03579, Republic of Korea
- Department of Advanced Materials Engineering, Chung-Ang University, 4726, Seodong-daero, Daedeok-myeon, Anseong-si, Gyeonggi-do, 17546, Republic of Korea
| | - Miri Choi
- Chuncheon Center, Korea Basic Science Institute, Chuncheon, 24341, Republic of Korea
| | - Cormac Ó Coileáin
- Institute of Physics, Faculty of Electrical Engineering and Information Technology, University of the Bundeswehr Munich, Neubiberg, 85577, Germany
| | - Kuan-Ming Hung
- Department of Electronics Engineering, National Kaohsiung University of Science and Technology, Kaohsiung, 807, Taiwan, ROC
| | - Ching-Ray Chang
- Quantum Information Center, Chung Yuan Christian University, Taoyuan, 32023, Taiwan, ROC
- Department of Physics, National Taiwan University, Taipei, 106, Taiwan, ROC
| | - Igor V Shvets
- School of Physics, Trinity College Dublin, Dublin, Dublin 2, Ireland
| | - Han-Chun Wu
- School of Physics, Beijing Institute of Technology, Beijing, 100081, P. R. China.
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5
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Qi W, Wu HC, Chan SC. MDF-Net: A Multi-Scale Dynamic Fusion Network for Breast Tumor Segmentation of Ultrasound Images. IEEE Trans Image Process 2023; 32:4842-4855. [PMID: 37639409 DOI: 10.1109/tip.2023.3304518] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/31/2023]
Abstract
Breast tumor segmentation of ultrasound images provides valuable information of tumors for early detection and diagnosis. Accurate segmentation is challenging due to low image contrast between areas of interest; speckle noises, and large inter-subject variations in tumor shape and size. This paper proposes a novel Multi-scale Dynamic Fusion Network (MDF-Net) for breast ultrasound tumor segmentation. It employs a two-stage end-to-end architecture with a trunk sub-network for multiscale feature selection and a structurally optimized refinement sub-network for mitigating impairments such as noise and inter-subject variation via better feature exploration and fusion. The trunk network is extended from UNet++ with a simplified skip pathway structure to connect the features between adjacent scales. Moreover, deep supervision at all scales, instead of at the finest scale in UNet++, is proposed to extract more discriminative features and mitigate errors from speckle noise via a hybrid loss function. Unlike previous works, the first stage is linked to a loss function of the second stage so that both the preliminary segmentations and refinement subnetworks can be refined together at training. The refinement sub-network utilizes a structurally optimized MDF mechanism to integrate preliminary segmentation information (capturing general tumor shape and size) at coarse scales and explores inter-subject variation information at finer scales. Experimental results from two public datasets show that the proposed method achieves better Dice and other scores over state-of-the-art methods. Qualitative analysis also indicates that our proposed network is more robust to tumor size/shapes, speckle noise and heavy posterior shadows along tumor boundaries. An optional post-processing step is also proposed to facilitate users in mitigating segmentation artifacts. The efficiency of the proposed network is also illustrated on the "Electron Microscopy neural structures segmentation dataset". It outperforms a state-of-the-art algorithm based on UNet-2022 with simpler settings. This indicates the advantages of our MDF-Nets in other challenging image segmentation tasks with small to medium data sizes.
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Hsieh YC, Wu HC, Chuang SS. Early T-cell precursor lymphoblastic leukaemia with monocytic morphology negative for CD3 by flow cytometry: A diagnostic challenge solved by immunohistochemistry. Malays J Pathol 2023; 45:297-298. [PMID: 37658540] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 09/03/2023]
Abstract
No abstract available.
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Affiliation(s)
- Y C Hsieh
- Chi-Mei Medical Center, Departments of Clinical Pathology, Tainan, Taiwan
| | - H C Wu
- Chi-Mei Medical Center, Departments of Internal Medicine, Tainan, Taiwan
| | - S S Chuang
- Chi-Mei Medical Center, Departments of Pathology, Tainan, Taiwan.
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7
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Zhang BF, Fang J, Zhang ZQ, Ao XL, Xia L, Wu HC, Zhang SA, Wu ZX, Li DL. [Factors influencing bilirubin elevation and its correlation with UGT1A1 gene polymorphism in the early postoperative period of transjugular intrahepatic portosystemic shunt]. Zhonghua Gan Zang Bing Za Zhi 2023; 31:524-531. [PMID: 37365030 DOI: 10.3760/cma.j.cn501113-20220527-00285] [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] [Grants] [Subscribe] [Scholar Register] [Indexed: 06/28/2023]
Abstract
Objective: To investigate the factors influencing total bilirubin elevation and its correlation with UGT1A1 gene polymorphism in the early postoperative period of transjugular intrahepatic portosystemic shunt (TIPS). Methods: 104 cases with portal hypertension and esophageal variceal hemorrhage (EVB) treated with elective TIPS treatment were selected as the study subjects and were divided into a bilirubin-elevated group and a normal bilirubin group according to the total bilirubin elevation level during the early postoperative period. Univariate analysis and logistic regression were used to analyze the factors influencing total bilirubin elevation in the early postoperative period. PCR amplification and first-generation sequencing technology were used to detect the polymorphic loci of the UGT1A1 gene promoter TATA box, enhancer c.-3279 T > G, c.211G > A, and c.686C > A. Logistic regression was used to analyze the correlation of four locus alleles and genotypes with elevated total bilirubin in the early postoperative period. Results: Among the 104 cases, 47 patients were in the bilirubin elevated group, including 35 males (74.5%) and 12 females (25.5%), aged (50.72 ± 12.56) years. There were 57 cases in the normal bilirubin group, including 42 males (73.7%) and 15 females (26.3%), aged (51.63 ± 11.10) years. There was no statistically significant difference in age (t = -0.391, P = 0.697) and gender (χ(2) = 0.008, P = 0.928) between the two groups of patients. Univariate analysis revealed that preoperative alanine transaminase (ALT) level (χ(2) = 5.954, P = 0.015), total bilirubin level (χ(2) = 16.638, P < 0.001), MELD score (χ(2) = 10.054, P = 0.018), Child-Pugh score (χ(2) = 6.844, P = 0.022), and postoperative portal vein branch development (χ(2) = 6.738, P = 0.034) were statistically significantly different between the two groups. Logistic regression analysis showed that preoperative ALT level, total bilirubin level, and portal vein branch development after TIPS were correlated with the elevated total bilirubin in the early postoperative period. The polymorphism of the c.211G > A locus of the UGT1A1 gene correlation had elevated total bilirubin in the early postoperative period of TIPS. The risk of elevated total bilirubin was increased in the population carrying allele A (P = 0.001, OR = 4.049) in the early postoperative period. Allelic polymorphisms in the TATA box promoter region and enhancer c.-3279 T > G and c.686C > A had no statistically significant difference between the bilirubin-elevated group and the normal bilirubin group. Conclusion: The preoperative ALT level, total bilirubin level, and portal vein branch development are correlated with the elevated total bilirubin in early postoperative patients. The polymorphisms of the UGT1A1 gene and enhancer c.211G > A are correlated with the occurrence of elevated total bilirubin in the early postoperative period of TIPS. Allele A carrier may have a higher risk of elevated total bilirubin in the early postoperative period.
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Affiliation(s)
- B F Zhang
- Department of Hepatobiliary Internal Medicine, Fuzong Clinical Medical College of Fujian Medical University/ the 900th Hospital of the Joint Logistics Support Force, Fuzhou 350025, China, Fuzhou 350025, China Zhao Bifeng is working on the Department of Gastroenterology, Quanzhou First Hospital Affiliated to Fujian Medical University, Quanzhou 362046, China
| | - J Fang
- Department of Hepatobiliary Internal Medicine, The Third People's Hospital of Fujian University of Traditional Chinese Medicine, Fuzhou 350108, China
| | - Z Q Zhang
- Department of Hepatobiliary Internal Medicine, Fuzong Clinical Medical College of Fujian Medical University/ the 900th Hospital of the Joint Logistics Support Force, Fuzhou 350025, China, Fuzhou 350025, China
| | - X L Ao
- Department of Hepatobiliary Internal Medicine, Fuzong Clinical Medical College of Fujian Medical University/ the 900th Hospital of the Joint Logistics Support Force, Fuzhou 350025, China, Fuzhou 350025, China
| | - L Xia
- Department of Hepatobiliary Internal Medicine, The Third People's Hospital of Fujian University of Traditional Chinese Medicine, Fuzhou 350108, China
| | - H C Wu
- Department of Hepatobiliary Internal Medicine, Fuzong Clinical Medical College of Fujian Medical University/ the 900th Hospital of the Joint Logistics Support Force, Fuzhou 350025, China, Fuzhou 350025, China
| | - S A Zhang
- Department of Hepatobiliary Internal Medicine, Fuzong Clinical Medical College of Fujian Medical University/ the 900th Hospital of the Joint Logistics Support Force, Fuzhou 350025, China, Fuzhou 350025, China
| | - Z X Wu
- Department of Hepatobiliary Internal Medicine, Fuzong Clinical Medical College of Fujian Medical University/ the 900th Hospital of the Joint Logistics Support Force, Fuzhou 350025, China, Fuzhou 350025, China
| | - D L Li
- Department of Hepatobiliary Internal Medicine, Fuzong Clinical Medical College of Fujian Medical University/ the 900th Hospital of the Joint Logistics Support Force, Fuzhou 350025, China, Fuzhou 350025, China
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Zhao Y, Wu G, Hung KM, Cho J, Choi M, Ó Coileáin C, Duesberg GS, Ren XK, Chang CR, Wu HC. Field Effect Transistor Gas Sensors Based on Mechanically Exfoliated Van der Waals Materials. ACS Appl Mater Interfaces 2023; 15:17335-17343. [PMID: 36972407 DOI: 10.1021/acsami.2c23086] [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: 06/18/2023]
Abstract
The high surface-to-volume ratio and flatness of mechanically exfoliated van der Waals (vdW) layered materials make them an ideal platform to investigate the Langmuir absorption model. In this work, we fabricated field effect transistor gas sensors, based on a variety of mechanically exfoliated vdW materials, and investigated their electrical field-dependent gas sensing properties. The good agreement between the experimentally extracted intrinsic parameters, such as equilibrium constant and adsorption energy, and theoretically predicted values suggests validity of the Langmuir absorption model for vdW materials. Moreover, we show that the device sensing behavior depends crucially on the availability of carriers, and giant sensitivities and strong selectivity can be achieved at the sensitivity singularity. Finally, we demonstrate that such features provide a fingerprint for different gases to quickly detect and differentiate between low concentrations of mixed hazardous gases using sensor arrays.
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Affiliation(s)
- Yue Zhao
- School of Physics, Beijing Institute of Technology, Beijing 100081, P. R. China
| | - Gang Wu
- School of Physics, Beijing Institute of Technology, Beijing 100081, P. R. China
| | - Kuan-Ming Hung
- Department of Electronics Engineering, National Kaohsiung University of Science and Technology, Kaohsiung, Taiwan 807, ROC
| | - Jiung Cho
- Western Seoul Center, Korea Basic Science Institute, Seoul 03579, Republic of Korea
| | - Miri Choi
- Chuncheon Center, Korea Basic Science Institute, Chuncheon 24341, Republic of Korea
| | - Cormac Ó Coileáin
- Institute of Physics, Faculty of Electrical Engineering and Information Technology (EIT 2) and Center for Integrated Sensor Systems, University of the Bundeswehr Munich, Neubiberg 85577, Germany
| | - Georg S Duesberg
- Institute of Physics, Faculty of Electrical Engineering and Information Technology (EIT 2) and Center for Integrated Sensor Systems, University of the Bundeswehr Munich, Neubiberg 85577, Germany
| | - Xiang-Kui Ren
- School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, P. R. China
| | - Ching-Ray Chang
- Quantum Information Center, Chung Yuan Christian University, Taoyuan, Taiwan 32023, ROC
- Department of Physics, National Taiwan University, Taipei, Taiwan 106, ROC
| | - Han-Chun Wu
- School of Physics, Beijing Institute of Technology, Beijing 100081, P. R. China
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9
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Huang HJ, Gao SY, Zhao AJ, Ngeontae W, Wu HC, Wang FM, Ren XK. Tetraphenylethylene sulfonate derivative as turn-on fluorescent sensor for berberine chloride detection in aqueous solution. J Pharm Biomed Anal 2022; 220:115030. [PMID: 36088810 DOI: 10.1016/j.jpba.2022.115030] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2022] [Revised: 08/30/2022] [Accepted: 09/03/2022] [Indexed: 11/26/2022]
Abstract
A negatively-charged tetraphenylethylene derivative (TPE-SE) was designed and synthesized as turn-on fluorescent sensor for berberine chloride (BBC) detection in aqueous solution. The fluorescent property and detection mechanism were elucidated by UV-vis absorption spectra, photoluminescence spectra, dynamic light scattering experiments. The results reveal that the BBC can lead to aggregation-induced emission of TPE-SE due to the electrostatic interactions, endowing TPE-SE with excellent turn-on detecting ability, high selectivity and sensitivity to BBC. The detection limit is as low as 6.58 × 10-6M. These results should be applicable to fabricate special turn-on fluorescent sensors towards various antibiotics, and it is crucially important for achieving reasonable control and intake of small biomolecules.
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Affiliation(s)
- Han-Jun Huang
- School of Chemical Engineering and Technology, State Key Laboratory of Chemical Engineering, Tianjin University, Tianjin 300350, PR China
| | - Si-Yu Gao
- School of Chemical Engineering and Technology, State Key Laboratory of Chemical Engineering, Tianjin University, Tianjin 300350, PR China
| | - Ai-Juan Zhao
- School of Chemical Engineering and Technology, State Key Laboratory of Chemical Engineering, Tianjin University, Tianjin 300350, PR China
| | - Wittaya Ngeontae
- Department of Chemistry, Faculty of Science, Khon Kaen University, Khon Kaen 40002, Thailand
| | - Han-Chun Wu
- School of Physics, Beijing Institute of Technology, Beijing 100081, PR China
| | - Fu-Min Wang
- School of Chemical Engineering and Technology, State Key Laboratory of Chemical Engineering, Tianjin University, Tianjin 300350, PR China.
| | - Xiang-Kui Ren
- School of Chemical Engineering and Technology, State Key Laboratory of Chemical Engineering, Tianjin University, Tianjin 300350, PR China; Guangdong Provincial Key Laboratory of Luminescence from Molecular Aggregates, South China University of Technology, Guangzhou 510640, PR China.
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10
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Zhao Y, Cho J, Choi M, Ó Coileáin C, Arora S, Hung KM, Chang CR, Abid M, Wu HC. Light-Tunable Polarity and Erasable Physisorption-Induced Memory Effect in Vertically Stacked InSe/SnS 2 Self-Powered Photodetector. ACS Nano 2022; 16:17347-17355. [PMID: 36153977 DOI: 10.1021/acsnano.2c08177] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
van der Waals heterojunctions with tunable polarity are being actively explored for more Moore and more-than-Moore device applications, as they can greatly simplify circuit design. However, inadequate control over the multifunctional operational states is still a challenge in their development. Here, we show that a vertically stacked InSe/SnS2 van der Waals heterojunction exhibits type-II band alignment, and its polarity can be tuned by an external electric field and by the wavelength and intensity of an illuminated light source. Moreover, such SnS2/InSe diodes are self-powered broadband photodetectors with good performance. The self-powered performance can be further enhanced significantly with gas adsorption, and the device can be quickly restored to the state before gas injection using a gate voltage pulse. Our results suggest a way to achieve and design multiple functions in a single device with multifield coupling of light, electrical field, gas, or other external stimulants.
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Affiliation(s)
- Yue Zhao
- School of Physics, Beijing Institute of Technology, Beijing 100081, P.R. China
| | - Jiung Cho
- Western Seoul Center, Korea Basic Science Institute, Seoul 03579, Republic of Korea
| | - Miri Choi
- Chuncheon Center, Korea Basic Science Institute, Chuncheon 24341, Republic of Korea
| | - Cormac Ó Coileáin
- Institute of Physics, EIT 2, Faculty of Electrical Engineering and Information Technology, University of the Bundeswehr Munich, Neubiberg 85577, Germany
| | - Sunil Arora
- Centre for Nanoscience and Nanotechnology, Panjab University, Chandigarh 160014, India
| | - Kuan-Ming Hung
- Department of Electronics Engineering, National Kaohsiung University of Science and Technology, Kaohsiung 807, Taiwan, ROC
| | - Ching-Ray Chang
- Quantum information center, Chung Yuan Christian University, Taoyuan 32023, Taiwan, ROC
- Department of Physics, National Taiwan University, Taipei 106, Taiwan, ROC
| | - Mohamed Abid
- School of Physics, Beijing Institute of Technology, Beijing 100081, P.R. China
| | - Han-Chun Wu
- School of Physics, Beijing Institute of Technology, Beijing 100081, P.R. China
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12
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Wu G, Chung HS, Bae TS, Cho J, Lee KC, Cheng HH, Coileáin CÓ, Hung KM, Chang CR, Wu HC. Efficient Suppression of Charge Recombination in Self-Powered Photodetectors with Band-Aligned Transferred van der Waals Metal Electrodes. ACS Appl Mater Interfaces 2021; 13:61799-61808. [PMID: 34927430 DOI: 10.1021/acsami.1c20499] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Recombination of photogenerated electron-hole pairs dominates the photocarrier lifetime and then influences the performance of photodetectors and solar cells. In this work, we report the design and fabrication of band-aligned van der Waals-contacted photodetectors with atomically sharp and flat metal-semiconductor interfaces through transferred metal integration. A unity factor α is achieved, which is essentially independent of the wavelength of the light, from ultraviolet to near-infrared, indicating effective suppression of charge recombination by the device. The short-circuit current (0.16 μA) and open-circuit voltage (0.72 V) of the band-aligned van der Waals-contacted devices are at least 1 order of magnitude greater than those of band-aligned deposited devices and 2 orders of magnitude greater than those of non-band-aligned deposited devices. High responsivity, detectivity, and polarization sensitivity ratio of 283 mA/W, 6.89 × 1012 cm Hz1/2 W-1, and 3.05, respectively, are also obtained for the device at zero bias. Moreover, the efficient suppression of charge recombination in our air-stable self-powered photodetectors also results in a fast response speed and leads to polarization-sensitive performance.
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Affiliation(s)
- Gang Wu
- School of Physics, Beijing Institute of Technology, Beijing 100081, P. R. China
| | - Hee-Suk Chung
- Jeonju Center, Korea Basic Science Institute, Jeonju 54896, Republic of Korea
| | - Tae-Sung Bae
- Jeonju Center, Korea Basic Science Institute, Jeonju 54896, Republic of Korea
| | - Jiung Cho
- Western Seoul Center, Korea Basic Science Institute, Seoul 03579, Republic of Korea
| | - Kuo-Chih Lee
- Center for Condensed Matter Sciences and Graduate Institute of Electronics Engineering, National Taiwan University, Taipei 106, Taiwan, ROC
| | - Hung Hsiang Cheng
- Center for Condensed Matter Sciences and Graduate Institute of Electronics Engineering, National Taiwan University, Taipei 106, Taiwan, ROC
| | - Cormac Ó Coileáin
- Institute of Physics, EIT 2, Faculty of Electrical Engineering and Information Technology, Universität der Bundeswehr München, Neubiberg 85579, Germany
| | - Kuan-Ming Hung
- Department of Electronics Engineering, National Kaohsiung University of Science and Technology, Kaohsiung 807, Taiwan, ROC
| | - Ching-Ray Chang
- Department of Physics, National Taiwan University, Taipei 106, Taiwan, ROC
| | - Han-Chun Wu
- School of Physics, Beijing Institute of Technology, Beijing 100081, P. R. China
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13
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Zhao Y, Tsai TY, Wu G, Ó Coileáin C, Zhao YF, Zhang D, Hung KM, Chang CR, Wu YR, Wu HC. Graphene/SnS 2 van der Waals Photodetector with High Photoresponsivity and High Photodetectivity for Broadband 365-2240 nm Detection. ACS Appl Mater Interfaces 2021; 13:47198-47207. [PMID: 34546715 DOI: 10.1021/acsami.1c11534] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [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
The fabrication of graphene/SnS2 van der Waals photodetectors and their photoelectrical properties are systematically investigated. It was found that a dry transferred graphene/SnS2 van der Waals heterostructure had a broadband sensing range from ultraviolet (365 nm) to near-infrared (2.24 μm) and respective improved responsivities and photodetectivities of 7.7 × 103 A/W and 8.9 × 1013 jones at 470 nm and 2 A/W and 1.8 × 1010 jones at 1064 nm. Moreover, positive and negative photoconductance effects were observed when the photodetectors were illuminated by photon sources with energies greater and smaller than the bandgap of SnS2, respectively. The photoresponsivity (R) versus incident power density (P) follows the empirical law R ∝ Pinβ, with β > -1 for positive photoconductance effects and β < -1 for negative photoconductance effects. On the basis of the Fowler-Nordheim tunneling model and a Poisson and drift-diffusion simulation, we show quantitatively that the barrier height and barrier width of the heterostructure photodetector could be controlled by a laser and an external electrical field through a photogating effect generated by carriers trapped at the interface, which could be used to tune the separation and transport of photogenerated carriers. Our results may be useful for the design of high performance van der Waals heterojunction photodetectors.
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Affiliation(s)
- Yue Zhao
- School of Physics, Beijing Institute of Technology, Beijing 100081, P. R. China
| | - Tsung-Yin Tsai
- Graduate Institute of Photonics and Optoelectronics and Department of Electrical Engineering, National Taiwan University, Taipei 10617, Taiwan
| | - Gang Wu
- School of Physics, Beijing Institute of Technology, Beijing 100081, P. R. China
| | - Cormac Ó Coileáin
- Centre for Research on Adaptive Nanostructures and Nanodevices (CRANN) and Advanced Materials and Bioengineering Research (AMBER), School Chemistry, Trinity College, Dublin, Ireland
| | - Yan-Feng Zhao
- School of Physics, Beijing Institute of Technology, Beijing 100081, P. R. China
| | - Duan Zhang
- Elementary Educational College, Beijing key Laboratory for Nano-Photonics and Nano-Structure, Capital Normal University, Beijing 100048, P. R. China
| | - Kuan-Ming Hung
- Department of Electronics Engineering, National Kaohsiung University of Science and Technology, Kaohsiung 807, Taiwan
| | - Ching-Ray Chang
- Department of Physics, National Taiwan University, Taipei 106, Taiwan
| | - Yuh-Renn Wu
- Graduate Institute of Photonics and Optoelectronics and Department of Electrical Engineering, National Taiwan University, Taipei 10617, Taiwan
| | - Han-Chun Wu
- School of Physics, Beijing Institute of Technology, Beijing 100081, P. R. China
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14
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Yan W, Fuh HR, Lv Y, Chen KQ, Tsai TY, Wu YR, Shieh TH, Hung KM, Li J, Zhang D, Ó Coileáin C, Arora SK, Wang Z, Jiang Z, Chang CR, Wu HC. Giant gauge factor of Van der Waals material based strain sensors. Nat Commun 2021; 12:2018. [PMID: 33795697 PMCID: PMC8016834 DOI: 10.1038/s41467-021-22316-8] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2020] [Accepted: 03/10/2021] [Indexed: 02/07/2023] Open
Abstract
There is an emergent demand for high-flexibility, high-sensitivity and low-power strain gauges capable of sensing small deformations and vibrations in extreme conditions. Enhancing the gauge factor remains one of the greatest challenges for strain sensors. This is typically limited to below 300 and set when the sensor is fabricated. We report a strategy to tune and enhance the gauge factor of strain sensors based on Van der Waals materials by tuning the carrier mobility and concentration through an interplay of piezoelectric and photoelectric effects. For a SnS2 sensor we report a gauge factor up to 3933, and the ability to tune it over a large range, from 23 to 3933. Results from SnS2, GaSe, GeSe, monolayer WSe2, and monolayer MoSe2 sensors suggest that this is a universal phenomenon for Van der Waals semiconductors. We also provide proof of concept demonstrations by detecting vibrations caused by sound and capturing body movements.
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Affiliation(s)
- Wenjie Yan
- School of Physics, Beijing Institute of Technology, Beijing, P. R. China
| | - Huei-Ru Fuh
- Department of Physics, National Taiwan University, Taipei, Taiwan
- Department of Chemical Engineering & Materials Science, Yuan Ze University, Taoyuan City, Taiwan
| | - Yanhui Lv
- School of Physics, Beijing Institute of Technology, Beijing, P. R. China
| | - Ke-Qiu Chen
- Department of Applied Physics, School of Physics and Electronics, Hunan University, Changsha, P. R. China
| | - Tsung-Yin Tsai
- Graduate Institute of Photonics and Optoelectronics and Department of Electrical Engineering, National Taiwan University, Taipei, Taiwan
| | - Yuh-Renn Wu
- Graduate Institute of Photonics and Optoelectronics and Department of Electrical Engineering, National Taiwan University, Taipei, Taiwan
| | - Tung-Ho Shieh
- Department of Intelligent Robotics Engineering, Kun-Shan University, Tainan, Taiwan
| | - Kuan-Ming Hung
- Department of Electronics Engineering, National Kaohsiung University of Science and Technology, Kaohsiung, Taiwan.
| | - Juncheng Li
- School of Physics, Beijing Institute of Technology, Beijing, P. R. China
| | - Duan Zhang
- Elementary Educational College, Beijing key Laboratory for Nano-Photonics and Nano-Structure, Capital Normal University, Beijing, P. R. China
| | - Cormac Ó Coileáin
- Centre for Research on Adaptive Nanostructures and Nanodevices (CRANN) and Advanced Materials and Bioengineering Research (AMBER), School Chemistry, Trinity College Dublin, Dublin, Ireland
| | - Sunil K Arora
- Centre for Nanoscience and Nanotechnology, Panjab University, Chandigarh, India
| | - Zhi Wang
- School of Physics, Beijing Institute of Technology, Beijing, P. R. China
| | - Zhaotan Jiang
- School of Physics, Beijing Institute of Technology, Beijing, P. R. China
| | - Ching-Ray Chang
- Department of Physics, National Taiwan University, Taipei, Taiwan
| | - Han-Chun Wu
- School of Physics, Beijing Institute of Technology, Beijing, P. R. China.
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15
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Wu HC, Shu W, Li ML, Li ZA, Hu YF. [Using text mining to identify gap in acquired immunodeficiency syndrome related information dissemination between the official channel delivery and the needs of adolescents]. Zhonghua Yu Fang Yi Xue Za Zhi 2020; 54:685-690. [PMID: 32842287 DOI: 10.3760/cma.j.cn112150-20190816-00663] [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] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Objective: The study intends to identify gap in HIV/AIDS awareness dissemination between the official channel delivery and the needs of adolescents. Methods: We crawled all the HIV/AIDS queries from "Baidu zhidao" till June 11st, 2018. "Baidu zhidao" inquiry and information form official public service announcement (abbreviated for "official delivery" hereafter) were the data source for comparative analysis. We categorized the text data into four kinds, "prevention", "testing and treatment", "symptoms and infection" and "legalization and policies" according to official categorization. Word segmentation was used for text mining and word frequency statistics, as well word cloud was used for word frequency visualization (all based on a comparison after removing the useless words). Results: Of the official delivery, the proportion of prevention category accounted for 32.3% (n=162) (ranks 1st), and the proportion of legalization and policies category was 14.1% (n=71). While among the "Baidu zhidao" inquiry information, the proportion of testing and treatment category accounted for 51.7% (n=51 264), and the proportion of prevention category accounted for 11.4% (n=11 272). The frequencies of same terms/ repeated terms of two channels accounted for 60% (59.3%-63.9%) of each category among the official delivery, of which, the proportion of interest terms comparatively less and more diverse in "Baidu zhidao" inquiries. The proportion of the terms frequency of each category was about 45% in "prevention, testing and treatment", 34.3% (n=14 781) in "symptoms and infection" and 17.0% (n=5 744) in "legalization and policies", respectively. Conclusion: A big gap was identified between the available official source and inquiries' term, especially word frequency discrepancy between "legalization and policies" and "prevention" categories. It underscore the necessity for the official channel to address the needs and interests of adolescents in the future.
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Affiliation(s)
- H C Wu
- Department of Child and Adolescent Health and Maternal Health, School of Public Health, Capital Medical University, Beijing 100069, China
| | - W Shu
- Department of Child and Adolescent Health and Maternal Health, School of Public Health, Capital Medical University, Beijing 100069, China
| | - M L Li
- Department of Child and Adolescent Health and Maternal Health, School of Public Health, Capital Medical University, Beijing 100069, China
| | - Z A Li
- Department of Child and Adolescent Health and Maternal Health, School of Public Health, Capital Medical University, Beijing 100069, China
| | - Yi-fei Hu
- Department of Child and Adolescent Health and Maternal Health, School of Public Health, Capital Medical University, Beijing 100069, China
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16
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Zhang D, Wu Y, Su YH, Hsu MC, Ó Coileáin C, Cho J, Choi M, Chun BS, Guo Y, Chang CR, Wu HC. Charge density waves and degenerate modes in exfoliated monolayer 2H-TaS 2. IUCrJ 2020; 7:913-919. [PMID: 32939283 PMCID: PMC7467171 DOI: 10.1107/s2052252520011021] [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] [Figures] [Subscribe] [Scholar Register] [Received: 06/01/2020] [Accepted: 08/11/2020] [Indexed: 06/11/2023]
Abstract
Charge density waves spontaneously breaking lattice symmetry through periodic lattice distortion, and electron-electron and electron-phonon inter-actions, can lead to a new type of electronic band structure. Bulk 2H-TaS2 is an archetypal transition metal dichalcogenide supporting charge density waves with a phase transition at 75 K. Here, it is shown that charge density waves can exist in exfoliated monolayer 2H-TaS2 and the transition temperature can reach 140 K, which is much higher than that in the bulk. The degenerate breathing and wiggle modes of 2H-TaS2 originating from the periodic lattice distortion are probed by optical methods. The results open an avenue to investigating charge density wave phases in two-dimensional transition metal dichalcogenides and will be helpful for understanding and designing devices based on charge density waves.
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Affiliation(s)
- Duan Zhang
- Elementary Educational College, Beijing Key Laboratory for Nano-Photonics and Nano-Structure, Capital Normal University, Beijing 100048, People’s Republic of China
- School of Physics, Beijing Institute of Technology, Beijing 100081, People’s Republic of China
| | - Yecun Wu
- School of Physics, Beijing Institute of Technology, Beijing 100081, People’s Republic of China
| | - Yu-Hsin Su
- Department of Physics, National Taiwan University, Taipei 106, Taiwan
| | - Ming-Chien Hsu
- Department of Physics, National Sun Yat-sen University, Kaohsiung 80424, Taiwan
| | - Cormac Ó Coileáin
- School of Physics, Beijing Institute of Technology, Beijing 100081, People’s Republic of China
| | - Jiung Cho
- Western Seoul Center, Korean Basic Science Institute, Seoul 03579, Republic of Korea
| | - Miri Choi
- Chuncheon Center, Korean Basic Science Institute, Chuncheon 24341, Republic of Korea
| | - Byong Sun Chun
- Division of Industrial Metrology, Korea Research Institute of Standards and Science, Daejeon 3050340, Republic of Korea
| | - Yao Guo
- School of Physics, Beijing Institute of Technology, Beijing 100081, People’s Republic of China
| | - Ching-Ray Chang
- Department of Physics, National Taiwan University, Taipei 106, Taiwan
| | - Han-Chun Wu
- School of Physics, Beijing Institute of Technology, Beijing 100081, People’s Republic of China
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17
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Chen SW, Chang ST, Hsieh YC, Kuo CC, Wu HC, Feng YH, Chuang SS. Frequent loss of CD10 expression in follicular lymphoma with leukaemic presentation. Malays J Pathol 2020; 42:237-243. [PMID: 32860376] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
INTRODUCTION Follicular lymphoma (FL) is usually a nodal lymphoma expressing CD10, rarely with leukaemic presentation (FL-LP). MATERIALS AND METHODS We searched for FL-LP in our institution from 2000 to 2018 and characterised the neoplastic cells by flow cytometry, immunohistochemistry and fluorescence in situ hybridization. Thirteen (6.1%) of 212 FL cases were FL-LP, all de novo neoplasms. The leukaemic cells were small in 12 cases and large in one. All had concurrent FL, mostly (92%; 12/13) low-grade. The single case with large leukaemic cells had a concurrent primary splenic low-grade FL and a double-hit large B-cell lymphoma in the marrow. RESULTS CD10 was expressed in the leukaemic cells in 38% (5/13) cases by flow cytometry and in 77% (10/13) cases in tumours (p= 0.0471). IGH/BCL2 reciprocal translocation was identified in 85% (11/13) cases. Most patients were treated with chemotherapy. In a median follow-up time of 36 months, nine patients were in complete remission. The 2- and 5-year survival rates were at 100% and 83%, respectively. In this study, we characterised a series of de novo FL-LP in Taiwan. All patients had concurrent nodal and/or tissue tumours, which might suggest that these patients seek medical help too late. CONCLUSION The lower CD10 expression rate by flow cytometry than by immunohistochemistry might be due to different epitopes for these assays. Alternatively, loss of CD10 expression might play a role in the pathogenesis of leukaemic change. The clinical course of FL-LP could be aggressive, but a significant proportion of the patients obtained complete remission with chemotherapy.
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Affiliation(s)
- S W Chen
- Lioying Chi-Mei Hospital, Department of Internal Medicine, Division of Hemato-Oncology, Tainan, Taiwan.
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18
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Yan W, Lv C, Zhang D, Chen Y, Zhang L, Ó Coileáin C, Wang Z, Jiang Z, Hung KM, Chang CR, Wu HC. Enhanced NO 2 Sensitivity in Schottky-Contacted n-Type SnS 2 Gas Sensors. ACS Appl Mater Interfaces 2020; 12:26746-26754. [PMID: 32426961 DOI: 10.1021/acsami.0c07193] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Layered materials are highly attractive in gas sensor research due to their extraordinary electronic and physicochemical properties. The development of cheaper and faster room-temperature detectors with high sensitivities especially in the parts per billion level is the main challenge in this rapidly developing field. Here, we show that sensitivity to NO2 (S) can be greatly improved by at least two orders of magnitude using an n-type electrode metal. Unconventionally for such devices, the ln(S) follows the classic Langmuir isotherm model rather than S as is for a p-type electrode metal. Excellent device sensitivities, as high as 13,000% for 9 ppm and 97% for 1 ppb NO2, are achieved with Mn electrodes at room temperature, which can be further tuned and enhanced with the application of a bias. Long-term stability, fast recovery, and strong selectivity toward NO2 are also demonstrated. Such impressive features provide a real solution for designing a practical high-performance layered material-based gas sensor.
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Affiliation(s)
- Wenjie Yan
- School of Physics, Beijing Institute of Technology, Beijing 100081, P. R. China
| | - Chengzhai Lv
- School of Physics, Beijing Institute of Technology, Beijing 100081, P. R. China
| | - Duan Zhang
- Elementary Educational College, Beijing key Laboratory for Nano-Photonics and Nano-Structure, Capital Normal University, Beijing 100048, P. R. China
| | - Yanhui Chen
- Institute of Microstructure and Property of Advanced Materials, Beijing University of Technology, Beijing, 100124, China
| | - Lei Zhang
- Foshan (Southern China) Institute for New Materials, Guangdong 528000, China
| | - Cormac Ó Coileáin
- CRANN and AMBER, School of Chemistry, Trinity College, Dublin Dublin 2, Ireland
| | - Zhi Wang
- School of Physics, Beijing Institute of Technology, Beijing 100081, P. R. China
| | - Zhaotan Jiang
- School of Physics, Beijing Institute of Technology, Beijing 100081, P. R. China
| | - Kuan-Ming Hung
- Department of Electronics Engineering, National Kaohsiung University of Science and Technology, Kaohsiung 807, Taiwan, ROC
| | - Ching-Ray Chang
- Department of Physics, National Taiwan University, Taipei 106, Taiwan
| | - Han-Chun Wu
- School of Physics, Beijing Institute of Technology, Beijing 100081, P. R. China
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19
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Xu H, Wei J, Zhou H, Feng J, Xu T, Du H, He C, Huang Y, Zhang J, Liu Y, Wu HC, Guo C, Wang X, Guang Y, Wei H, Peng Y, Jiang W, Yu G, Han X. High Spin Hall Conductivity in Large-Area Type-II Dirac Semimetal PtTe 2. Adv Mater 2020; 32:e2000513. [PMID: 32176423 DOI: 10.1002/adma.202000513] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2020] [Revised: 03/02/2020] [Accepted: 03/03/2020] [Indexed: 05/17/2023]
Abstract
Manipulation of magnetization by electric-current-induced spin-orbit torque (SOT) is of great importance for spintronic applications because of its merits in energy-efficient and high-speed operation. An ideal material for SOT applications should possess high charge-spin conversion efficiency and high electrical conductivity. Recently, transition metal dichalcogenides (TMDs) emerge as intriguing platforms for SOT study because of their controllability in spin-orbit coupling, conductivity, and energy band topology. Although TMDs show great potentials in SOT applications, the present study is restricted to the mechanically exfoliated samples with small sizes and relatively low conductivities. Here, a manufacturable recipe is developed to fabricate large-area thin films of PtTe2 , a type-II Dirac semimetal, to study their capability of generating SOT. Large SOT efficiency together with high conductivity results in a giant spin Hall conductivity of PtTe2 thin films, which is the largest value among the presently reported TMDs. It is further demonstrated that the SOT from PtTe2 layer can switch a perpendicularly magnetized CoTb layer efficiently. This work paves the way for employing PtTe2 -like TMDs for wafer-scale spintronic device applications.
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Affiliation(s)
- Hongjun Xu
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing, 100190, China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, 100049, China
- Songshan Lake Materials Laboratory, Dongguan, Guangdong, 523808, China
| | - Jinwu Wei
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing, 100190, China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, 100049, China
- Songshan Lake Materials Laboratory, Dongguan, Guangdong, 523808, China
| | - Hengan Zhou
- State Key Laboratory of Low-Dimensional Quantum Physics, and Department of Physics, Tsinghua University, Beijing, 100084, China
- Collaborative Innovation Center of Quantum Matter, Beijing, 100084, China
| | - Jiafeng Feng
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing, 100190, China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Teng Xu
- State Key Laboratory of Low-Dimensional Quantum Physics, and Department of Physics, Tsinghua University, Beijing, 100084, China
- Collaborative Innovation Center of Quantum Matter, Beijing, 100084, China
| | - Haifeng Du
- High Magnetic Field Laboratory, Chinese Academy of Sciences, 350 Shushanhu Road, Hefei, Anhui, 230031, China
| | - Congli He
- Institute of Advanced Materials, Beijing Normal University, Beijing, 100875, China
| | - Yuan Huang
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing, 100190, China
| | - Junwei Zhang
- Key Laboratory of Magnetism and Magnetic Materials of the Ministry of Education, School of Physical Science and Technology and Electron Microscopy Centre of Lanzhou University, Lanzhou University, Lanzhou, 730000, China
| | - Yizhou Liu
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing, 100190, China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Han-Chun Wu
- School of Physics, Beijing Institute of Technology, Beijing, 100081, China
| | - Chenyang Guo
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing, 100190, China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Xiao Wang
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing, 100190, China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Yao Guang
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing, 100190, China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Hongxiang Wei
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing, 100190, China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Yong Peng
- Key Laboratory of Magnetism and Magnetic Materials of the Ministry of Education, School of Physical Science and Technology and Electron Microscopy Centre of Lanzhou University, Lanzhou University, Lanzhou, 730000, China
| | - Wanjun Jiang
- State Key Laboratory of Low-Dimensional Quantum Physics, and Department of Physics, Tsinghua University, Beijing, 100084, China
- Collaborative Innovation Center of Quantum Matter, Beijing, 100084, China
| | - Guoqiang Yu
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing, 100190, China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, 100049, China
- Songshan Lake Materials Laboratory, Dongguan, Guangdong, 523808, China
| | - Xiufeng Han
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing, 100190, China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, 100049, China
- Songshan Lake Materials Laboratory, Dongguan, Guangdong, 523808, China
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20
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Lv C, Yan W, Shieh TH, Zhao Y, Wu G, Zhao Y, Lv Y, Zhang D, Chen Y, Arora SK, Ó Coileáin C, Chang CR, Cheng HH, Hung KM, Wu HC. Electrical Contact Barriers between a Three-Dimensional Metal and Layered SnS 2. ACS Appl Mater Interfaces 2020; 12:15830-15836. [PMID: 32134622 DOI: 10.1021/acsami.9b21996] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [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
Field-effect transistors derived from traditional 3D semiconductors are rapidly approaching their fundamental limits. Layered semiconducting materials have emerged as promising candidates to replace restrictive 3D semiconductor materials. However, contacts between metals and layered materials deviate from Schottky-Mott behavior when determined by transport methods, while X-ray photoelectron spectroscopy measurements suggest that the contacts should be at the Schottky limit. Here, we present a systematic investigation on the influence of metal selection when electrically contacting SnS2, a layered metal dichalcogenide semiconductor with the potential to replace silicon. It is found that the electrically measured barrier height depends also weakly on the work function of the metal contacts with slopes of 0.09 and -0.34 for n-type and p-type Schottky contacts, respectively. Based on the Kirchhoff voltage law and considering a current path induced by metallic defects, we found that the Schottky barrier still follows the Schottky-Mott limits and the electrically measured barrier height mainly originates from the van der Waals gap between the metal and SnS2, and the slope depends on the magnitude of the van der Waals capacitance.
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Affiliation(s)
- Chengzhai Lv
- School of Physics, Beijing Institute of Technology, Beijing 100081, P. R. China
| | - Wenjie Yan
- School of Physics, Beijing Institute of Technology, Beijing 100081, P. R. China
| | - Tung-Ho Shieh
- Department of Computer and Communication, Kun Shan University, Tainan 710, Taiwan, ROC
| | - Yue Zhao
- School of Physics, Beijing Institute of Technology, Beijing 100081, P. R. China
| | - Gang Wu
- School of Physics, Beijing Institute of Technology, Beijing 100081, P. R. China
| | - Yanfeng Zhao
- School of Physics, Beijing Institute of Technology, Beijing 100081, P. R. China
| | - Yanhui Lv
- School of Physics, Beijing Institute of Technology, Beijing 100081, P. R. China
| | - Duan Zhang
- Elementary Educational College, Beijing key Laboratory for Nano-Photonics and Nano-Structure, Capital Normal University, Beijing 100048, P. R. China
| | - Yanhui Chen
- Institute of Microstructure and Property of Advanced Materials, Beijing University of Technology, Beijing 100124, China
| | - Sunil K Arora
- Centre for Nano Science and Nano Technology, Panjab University, Chandigarh 160014, India
| | - Cormac Ó Coileáin
- AMBER and CRANN, School of Chemistry, Trinity College Dublin, Dublin 2, Ireland
| | - Ching-Ray Chang
- Department of Physics, National Taiwan University, Taipei 106, Taiwan, ROC
| | - Hung Hsiang Cheng
- Center for Condensed Matter Sciences and Graduate Institute of Electronics Engineering, National Taiwan University, Taipei 106, Taiwan, ROC
| | - Kuan-Ming Hung
- Department of Electronics Engineering, National Kaohsiung University of Science and Technology, Kaohsiung 807, Taiwan, ROC
| | - Han-Chun Wu
- School of Physics, Beijing Institute of Technology, Beijing 100081, P. R. China
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21
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Wu HC, Rui Z, Lin JY. Hydrogen production with carbon dioxide capture by dual-phase ceramic-carbonate membrane reactor via steam reforming of methane. J Memb Sci 2020. [DOI: 10.1016/j.memsci.2019.117780] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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22
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Lv Y, Li H, Ó Coileáin C, Zhang D, Heng C, Chang CR, Hung KM, Cheng HH, Wu HC. Photoelectrical properties of graphene/doped GeSn vertical heterostructures. RSC Adv 2020; 10:20921-20927. [PMID: 35517749 PMCID: PMC9054288 DOI: 10.1039/d0ra04308g] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [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: 05/14/2020] [Accepted: 05/28/2020] [Indexed: 11/21/2022] Open
Abstract
GeSn is a group IV alloy material with a narrow bandgap, making it favorable for applications in sensing and imaging. However, strong surface carrier recombination is a limiting factor. To overcome this, we investigate the broadband photoelectrical properties of graphene integrated with doped GeSn, from the visible to the near infrared. It is found that photo-generated carriers can be separated and transported with a higher efficiency by the introduction of the graphene layer. Considering two contrasting arrangements of graphene on p-type and n-type GeSn films, photocurrents were suppressed in graphene/p-type GeSn heterostructures but enhanced in graphene/n-type GeSn heterostructures when compared with control samples without graphene. Moreover, the enhancement (suppression) factor increases with excitation wavelength but decreases with laser power. An enhancement factor of 4 is achieved for an excitation wavelength of 1064 nm. Compared with previous studies, it is found that our graphene/n-type GeSn based photodetectors provide a much wider photodetection range, from 532 nm to 1832 nm, and maintain comparable responsivity. Our experimental findings highlight the importance of the induced bending profile on the charge separation and provides a way to design high performance broadband photodetectors. The photoelectrical properties of graphene integrated with doped GeSn have been investigated and a high performance broadband photodetection can be achieved by integration of graphene with n-type GeSn.![]()
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Affiliation(s)
- Yanhui Lv
- School of Physics
- Beijing Institute of Technology
- Beijing 100081
- P. R. China
| | - Hui Li
- Center for Condensed Matter Sciences
- Graduate Institute of Electronics Engineering
- National Taiwan University
- Taipei 106
- ROC
| | - Cormac Ó Coileáin
- CRANN and AMBER
- School of Chemistry
- Trinity College Dublin
- Dublin 2
- Ireland
| | - Duan Zhang
- Elementary Educational College
- Beijing Key Laboratory for Nano-Photonics and Nano-Structure
- Capital Normal University
- Beijing 100048
- P. R. China
| | - Chenglin Heng
- School of Physics
- Beijing Institute of Technology
- Beijing 100081
- P. R. China
| | | | - K.-M. Hung
- Department of Electronics Engineering
- National Kaohsiung University of Science and Technology
- Kaohsiung 807
- ROC
| | - Huang Hsiang Cheng
- Center for Condensed Matter Sciences
- Graduate Institute of Electronics Engineering
- National Taiwan University
- Taipei 106
- ROC
| | - Han-Chun Wu
- School of Physics
- Beijing Institute of Technology
- Beijing 100081
- P. R. China
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23
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Li J, Yan W, Lv Y, Leng J, Zhang D, Ó Coileáin C, Cullen CP, Stimpel-Lindner T, Duesberg GS, Cho J, Choi M, Chun BS, Zhao Y, Lv C, Arora SK, Wu HC. Sub-millimeter size high mobility single crystal MoSe2 monolayers synthesized by NaCl-assisted chemical vapor deposition. RSC Adv 2020; 10:1580-1587. [PMID: 35494696 PMCID: PMC9048230 DOI: 10.1039/c9ra09103c] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [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: 11/04/2019] [Accepted: 12/26/2019] [Indexed: 01/11/2023] Open
Abstract
Monolayer MoSe2 is a transition metal dichalcogenide with a narrow bandgap, high optical absorbance and large spin-splitting energy, giving it great promise for applications in the field of optoelectronics. Producing monolayer MoSe2 films in a reliable and scalable manner is still a challenging task as conventional chemical vapor deposition (CVD) or exfoliation based techniques are limited due to the small domains/nanosheet sizes obtained. Here, based on NaCl assisted CVD, we demonstrate the simple and stable synthesis of sub-millimeter size single-crystal MoSe2 monolayers with mobilities ranging from 38 to 8 cm2 V−1 s−1. The average mobility is 12 cm2 V−1 s−1. We further determine that the optical responsivity of monolayer MoSe2 is 42 mA W−1, with an external quantum efficiency of 8.22%. Sub-millimeter single crystal MoSe2 monolayers with a mobility of 38 cm2 V−1 s−1 and responsivity of 42 mA W−1 were synthesized by NaCl-assisted chemical vapor deposition.![]()
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24
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Wei-Ting C, Feng YH, Kuo YH, Chen WY, Huang CT, Wu HC, Wang WC, Liao CT, Chen ZC. P1569The Impact of Multidisciplinary Cardio-Oncology Program on the Cardiovascular Outcomes in Breast Cancer Patients. Eur Heart J 2019. [DOI: 10.1093/eurheartj/ehz748.0329] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Abstract
Background
Chemo- and target therapies may induce myocardial dysfunction and lead to poor prognoses. Early detection of minor myocardial dysfunction is important for the prevention of subsequent cardiotoxicity. Cardio-oncology is a multidisciplinary field focusing on managing and preventing cardiovascular complications in cancer patients. However, whether Cardio-oncology program truly makes difference in cardiovascular outcomes remains unknown. Herein, we are sharing our experiences in our Medical Center.
Methods
Since 2014 till 2017, we recruited 154 patients with newly diagnosed breast cancer preparing for Epirubicin therapy. Echocardiography, biomarkers, six minute walking distance and cardiovascular adverse events including new onset of hypertension, stroke, myocardial infarction (MI) and mortality were recorded at baseline, three months, six months and one year. Any functional decline was reported to oncologists for the consideration of changing regimens. Otherwise, cardiologists would be consulted for cardiovascular educations and therapies. The echocardiographic and clinical records of 450 breast patients receiving Epirubicin therapy during 2010 to 2013 were also collected as comparison.
Results
Compared with the ratio of 20% patients receiving echocardiography prior to 2014, the ratio increased to 100% since Cardio-Oncology program started. Also, the drop of left ventricular ejection fraction (LVEF) from 25% attenuated to 5%. Before Cardio-Oncology Program, there were 1.7% of new onset hypertension, 0.8% of MI, 0.8% of stroke and 16.8% of mortality. Conversely, after the program, there were only 0.6% of new onset hypertension while no other cardiovascular complications were reported. Furthermore, compared with previous reports of the effectiveness of Cardio-Oncology Program, our result also displayed a superior impact on the cardiovascular outcomes.
Conclusions
Collectively, through a comprehensive monitoring and an early intervention of myocardial dysfunction post chemotherapies, Cardio-Oncology Program truly decreased the cardiovascular complications in breast cancer patients.
Acknowledgement/Funding
Chi-Mei Medical Center
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Affiliation(s)
- C Wei-Ting
- Chi-Mei Medical Center, Cardiology, Tainan, Taiwan
| | - Y H Feng
- Chi-Mei Medical Center, Oncology, Tainan, Taiwan
| | - Y H Kuo
- Chi-Mei Medical Center, Oncology, Tainan, Taiwan
| | - W Y Chen
- Chi-Mei Medical Center, Oncology, Tainan, Taiwan
| | - C T Huang
- Chi-Mei Medical Center, Oncology, Tainan, Taiwan
| | - H C Wu
- Chi-Mei Medical Center, Oncology, Tainan, Taiwan
| | - W C Wang
- Chi-Mei Medical Center, Surgery, Tainan, Taiwan
| | - C T Liao
- Chi-Mei Medical Center, Cardiology, Tainan, Taiwan
| | - Z C Chen
- Chi-Mei Medical Center, Cardiology, Tainan, Taiwan
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25
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Camargo Moreira ÓL, Cheng WY, Fuh HR, Chien WC, Yan W, Fei H, Xu H, Zhang D, Chen Y, Zhao Y, Lv Y, Wu G, Lv C, Arora SK, Ó Coileáin C, Heng C, Chang CR, Wu HC. High Selectivity Gas Sensing and Charge Transfer of SnSe 2. ACS Sens 2019; 4:2546-2552. [PMID: 31456397 DOI: 10.1021/acssensors.9b01461] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
SnSe2 is an anisotropic binary-layered material with rich physics, which could see it used for a variety of potential applications. Here, we investigate the gas-sensing properties of SnSe2 using first-principles calculations and verify predictions using a gas sensor made of few-layer SnSe2 grown by chemical vapor deposition. Theoretical simulations indicate that electrons transfer from SnSe2 to NO2, whereas the direction of charge transfer is the opposite for NH3. Notably, a flat molecular band appears around the Fermi energy after NO2 adsorption and the induced molecular band is close to the conduction band minimum. Moreover, compared with NH3, NO2 molecules adsorbed on SnSe2 have a lower adsorption energy and a higher charge transfer value. The dynamic-sensing responses of SnSe2 sensors confirm the theoretical predictions. The good match between the theoretical prediction and experimental demonstration suggests that the underlying sensing mechanism is related to the charge transfer and induced flat band. Our results provide a guideline for designing high-performance gas sensors based on SnSe2.
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Affiliation(s)
| | | | - Huei-Ru Fuh
- Department of Chemical Engineering & Materials Science, Yuan Ze University, Taoyuan City 320, Taiwan, ROC
| | | | - Wenjie Yan
- School of Physics, Beijing Institute of Technology, Beijing 100081, P. R. China
| | - Haifeng Fei
- School of Physics, Beijing Institute of Technology, Beijing 100081, P. R. China
| | - Hongjun Xu
- School of Physics, Beijing Institute of Technology, Beijing 100081, P. R. China
| | - Duan Zhang
- Elementary Educational College, Beijing Key Laboratory for Nano-Photonics and Nano-Structure, Capital Normal University, Beijing 100048, P. R. China
| | - Yanhui Chen
- Institute of Microstructure and Property of Advanced Materials, Beijing University of Technology, Beijing 100124, China
| | - Yanfeng Zhao
- School of Physics, Beijing Institute of Technology, Beijing 100081, P. R. China
| | - Yanhui Lv
- School of Physics, Beijing Institute of Technology, Beijing 100081, P. R. China
| | - Gang Wu
- School of Physics, Beijing Institute of Technology, Beijing 100081, P. R. China
| | - Chengzhai Lv
- School of Physics, Beijing Institute of Technology, Beijing 100081, P. R. China
| | - Sunil K. Arora
- Centre for Nano Science and Nano Technology, Panjab University, Chandigarh160014, India
| | - Cormac Ó Coileáin
- School of Physics, Beijing Institute of Technology, Beijing 100081, P. R. China
- Centre for Research on Adaptive Nanostructures and Nanodevices (CRANN) and Advanced Materials and Bioengineering Research (AMBER), School Chemistry, Trinity College Dublin, Dublin 2, Ireland
| | - Chenglin Heng
- School of Physics, Beijing Institute of Technology, Beijing 100081, P. R. China
| | | | - Han-Chun Wu
- School of Physics, Beijing Institute of Technology, Beijing 100081, P. R. China
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26
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Fei H, Wu G, Cheng WY, Yan W, Xu H, Zhang D, Zhao Y, Lv Y, Chen Y, Zhang L, Ó Coileáin C, Heng C, Chang CR, Wu HC. Enhanced NO 2 Sensing at Room Temperature with Graphene via Monodisperse Polystyrene Bead Decoration. ACS Omega 2019; 4:3812-3819. [PMID: 31459592 PMCID: PMC6648470 DOI: 10.1021/acsomega.8b03540] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/17/2018] [Accepted: 02/06/2019] [Indexed: 05/23/2023]
Abstract
Graphene is a single layer of carbon atoms with a large surface-to-volume ratio, providing a large capacity gas molecule adsorption and a strong surface sensitivity. Chemical vapor deposition-grown graphene-based NO2 gas sensors typically have detection limits from 100 parts per billion (ppb) to a few parts per million (ppm), with response times over 1000 s. Numerous methods have been proposed to enhance the NO2 sensing ability of graphenes. Among them, surface decoration with metal particles and metal-oxide particles has demonstrated the potential to enhance the gas-sensing properties. Here, we show that the NO2 sensing of graphene can be also enhanced via decoration with monodisperse polymer beads. In dark conditions, the detection limit is improved from 1000 to 45 ppb after the application of polystyrene (PS) beads. With laser illumination, a detection limit of 0.5 ppb is determined. The enhanced gas sensing is due to surface plasmon polaritons excited by interference and charge transfer between the PS beads. This method opens an interesting route for the application of graphene in gas sensing.
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Affiliation(s)
- Haifeng Fei
- School
of Physics, Beijing Institute of Technology, Beijing 100081, P. R. China
| | - Gang Wu
- School
of Materials Science and Engineering, Tongji
University, Shanghai 201804, P. R. China
| | - Wei-Ying Cheng
- Graduate Institute of Applied Physics and Department of Physics, National Taiwan University, Taipei 106, Taiwan
| | - Wenjie Yan
- School
of Physics, Beijing Institute of Technology, Beijing 100081, P. R. China
| | - Hongjun Xu
- School
of Physics, Beijing Institute of Technology, Beijing 100081, P. R. China
| | - Duan Zhang
- Elementary
Educational College, Beijing Key Laboratory for Nano-Photonics and
Nano-Structure, Capital Normal University, Beijing 100048, P. R. China
| | - Yanfeng Zhao
- School
of Physics, Beijing Institute of Technology, Beijing 100081, P. R. China
| | - Yanhui Lv
- School
of Physics, Beijing Institute of Technology, Beijing 100081, P. R. China
| | - Yanhui Chen
- Institute
of Microstructure and Property of Advanced Materials, Beijing University of Technology, Beijing 100124, China
| | - Lei Zhang
- School of
Chemical Engineering and Technology, Tianjin
University, Tianjin 300072, P. R. China
| | - Cormac Ó Coileáin
- School
of Physics, Beijing Institute of Technology, Beijing 100081, P. R. China
| | - Chenglin Heng
- School
of Physics, Beijing Institute of Technology, Beijing 100081, P. R. China
| | - Ching-Ray Chang
- Graduate Institute of Applied Physics and Department of Physics, National Taiwan University, Taipei 106, Taiwan
| | - Han-Chun Wu
- School
of Physics, Beijing Institute of Technology, Beijing 100081, P. R. China
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27
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Huang JR, Lee MH, Li WS, Wu HC. Liposomal Irinotecan for Treatment of Colorectal Cancer in a Preclinical Model. Cancers (Basel) 2019; 11:cancers11030281. [PMID: 30818855 PMCID: PMC6468623 DOI: 10.3390/cancers11030281] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [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: 01/26/2019] [Revised: 02/21/2019] [Accepted: 02/22/2019] [Indexed: 12/24/2022] Open
Abstract
Colorectal cancer (CRC) is the most frequently diagnosed cancer and leading cause of cancer-related deaths worldwide. Because of the use of first-line CRC treatments, such as irinotecan (IRI), is hindered by dose-limiting side effects, improved drug delivery systems may have major clinical benefits for CRC treatment. In this study, we generate and characterize liposomal irinotecan (Lipo-IRI), a lipid-based nanoparticle, which shows excellent bioavailability and pharmacokinetics. Additionally, this formulation allows IRI to be maintained in active form and prolongs its half-life in circulation compared to IRI in solution. Compared with IRI statistically, the level of prostaglandin E2 (PGE2) in colonic tissue decreases, and Bifidobacterium spp. (beneficial intestinal microbiota) content increases in the Lipo-IRI-treated group. Moreover, no damage is observed by the hematoxylin and eosin staining of the normal tissue samples from the Lipo-IRI-treated group. In a xenograft mouse model, CRC tumors shrink markedly following Lipo-IRI treatment, and mice receiving a targeted combination of Lipo-IRI and liposomal doxorubicin (Lipo-Dox) extend their survival rate significantly. Overall, our results demonstrate that this formulation of Lipo-IRI shows a great potential for the treatment of colorectal cancer.
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Affiliation(s)
- Jiao-Ren Huang
- Ph.D. program for Cancer Molecular Biology and Drug Discovery, College of Medical Science and Technology, Taipei Medical University and Academia Sinica, Taipei 110, Taiwan.
- Institute of Cellular and Organismic Biology, Academia Sinica, Taipei 115, Taiwan.
| | - Mei-Hsien Lee
- Graduate Institute of Pharmacognosy, College of Pharmacy, Taipei Medical University, Taipei 110, Taiwan.
| | - Wen-Shan Li
- Institute of Chemistry, Academia Sinica, Taipei 115, Taiwan.
| | - Han-Chun Wu
- Institute of Cellular and Organismic Biology, Academia Sinica, Taipei 115, Taiwan.
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28
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Xu H, Huang HP, Fei H, Feng J, Fuh HR, Cho J, Choi M, Chen Y, Zhang L, Chen D, Zhang D, Coileáin CÓ, Han X, Chang CR, Wu HC. Strategy for Fabricating Wafer-Scale Platinum Disulfide. ACS Appl Mater Interfaces 2019; 11:8202-8209. [PMID: 30729782 DOI: 10.1021/acsami.8b19218] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
PtS2 is a newly developed group 10 2D layered material with high carrier mobility, wide band gap tunability, strongly bound excitons, symmetrical metallic and magnetic edge states, and ambient stability, making it attractive in nanoelectronic, optoelectronic, and spintronic fields. To the aim of application, a large-scale synthesis is necessary. For transition-metal dichalcogenide (TMD) compounds, a thermally assisted conversion method has been widely used to fabricate wafer-scale thin films. However, PtS2 cannot be easily synthesized using the method, as the tetragonal PtS phase is more stable. Here, we use a specified quartz part to locally increase the vapor pressure of sulfur in a chemical vapor deposition furnace and successfully extend this method for the synthesis of PtS2 thin films in a scalable and controllable manner. Moreover, the PtS and PtS2 phases can be interchangeably converted through a proposed strategy. Field-effect transistor characterization and photocurrent measurements suggest that PtS2 is an ambipolar semiconductor with a narrow band gap. Moreover, PtS2 also shows excellent gas-sensing performance with a detection limit of ∼0.4 ppb for NO2. Our work presents a relatively simple way of synthesizing PtS2 thin films and demonstrates their promise for high-performance ultrasensitive gas sensing, broadband optoelectronics, and nanoelectronics in a scalable manner. Furthermore, the proposed strategy is applicable for making other PtX2 compounds and TMDs which are compatible with modern silicon technologies.
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Affiliation(s)
- Hongjun Xu
- School of Physics , Beijing Institute of Technology , Beijing 100081 , People's Republic of China
| | - Hsin-Pan Huang
- Graduate Institute of Applied Physics , National Taiwan University , Taipei 106 , Taiwan
| | - HaiFeng Fei
- School of Physics , Beijing Institute of Technology , Beijing 100081 , People's Republic of China
| | - Jiafeng Feng
- Beijing National Laboratory of Condensed Matter Physics, Institute of Physics, University of Chinese Academy of Sciences , Chinese Academy of Sciences , Beijing 100190 , P. R. China
| | - Huei-Ru Fuh
- Department of Chemical Engineering & Materials Science , Yuan Ze University , Taoyuan City 320 , Taiwan
| | - Jiung Cho
- Western Seoul Center , Korea Basic Science Institute , Seoul 03579 , Republic of Korea
| | - Miri Choi
- Chuncheon Center , Korea Basic Science Institute , Chuncheon 24341 , Republic of Korea
| | - Yanhui Chen
- Institute of Microstructure and Property of Advanced Materials , Beijing University of Technology , Beijing 100124 , China
| | - Lei Zhang
- School of Chemical Engineering and Technology , Tianjin University , Tianjin 300072 , P. R. China
| | - Dengyun Chen
- School of Physics , Beijing Institute of Technology , Beijing 100081 , People's Republic of China
| | - Duan Zhang
- School of Physics , Beijing Institute of Technology , Beijing 100081 , People's Republic of China
| | - Cormac Ó Coileáin
- School of Physics , Beijing Institute of Technology , Beijing 100081 , People's Republic of China
- School of Chemistry, AMBER and CRANN , Trinity College Dublin , Dublin 2 , Ireland
| | - Xiufeng Han
- Beijing National Laboratory of Condensed Matter Physics, Institute of Physics, University of Chinese Academy of Sciences , Chinese Academy of Sciences , Beijing 100190 , P. R. China
| | - Ching-Ray Chang
- Graduate Institute of Applied Physics , National Taiwan University , Taipei 106 , Taiwan
- Department of Physics , National Taiwan University , Taipei 106 , Taiwan
| | - Han-Chun Wu
- School of Physics , Beijing Institute of Technology , Beijing 100081 , People's Republic of China
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29
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Yan WJ, Chen DY, Fuh HR, Li YL, Zhang D, Liu H, Wu G, Zhang L, Ren X, Cho J, Choi M, Chun BS, Coileáin CÓ, Xu HJ, Wang Z, Jiang Z, Chang CR, Wu HC. Photo-enhanced gas sensing of SnS2 with nanoscale defects. RSC Adv 2019; 9:626-635. [PMID: 35517585 PMCID: PMC9059496 DOI: 10.1039/c8ra08857h] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [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: 10/25/2018] [Accepted: 12/20/2018] [Indexed: 11/21/2022] Open
Abstract
Recently a SnS2 based NO2 gas sensor with a 30 ppb detection limit was demonstrated but this required high operation temperatures. Concurrently, SnS2 grown by chemical vapor deposition is known to naturally contain nanoscale defects, which could be exploited. Here, we significantly enhance the performance of a NO2 gas sensor based on SnS2 with nanoscale defects by photon illumination, and a detection limit of 2.5 ppb is achieved at room temperature. Using a classical Langmuir model and density functional theory simulations, we show S vacancies work as additional adsorption sites with fast adsorption times, higher adsorption energies, and an order of magnitude higher resistance change compared with pristine SnS2. More interestingly, when electron–hole pairs are excited by photon illumination, the average adsorption time first increases and then decreases with NO2 concentration, while the average desorption time always decreases with NO2 concentration. Our results give a deep understanding of photo-enhanced gas sensing of SnS2 with nanoscale defects, and thus open an interesting window for the design of high performance gas sensing devices based on 2D materials. A photon assisted SnS2-based gas sensor with an ultra-high sensitivity of 3 ppb NO2 has been achieved at room temperature.![]()
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30
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Wu HC, Lin YS. Correction to “Effects of Oxygen Vacancy Order–Disorder Phase Transition on Air Separation by Perovskite Sorbents”. Ind Eng Chem Res 2018. [DOI: 10.1021/acs.iecr.8b06099] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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31
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32
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Affiliation(s)
- Tianjia Chen
- Collaborative
Innovation Centre of Chemical Science and Engineering (Tianjin), Tianjin
Key Laboratory of Catalysis Science and Technology and State Key Laboratory
for Chemical Engineering (Tianjin University), School of Chemical
Engineering, Tianjin University, Tianjin 300072, China
| | - Han-Chun Wu
- School
for Engineering of Matter, Transport and Energy, Arizona State University, Tempe, Arizona 85287, United States
| | - Yongdan Li
- Collaborative
Innovation Centre of Chemical Science and Engineering (Tianjin), Tianjin
Key Laboratory of Catalysis Science and Technology and State Key Laboratory
for Chemical Engineering (Tianjin University), School of Chemical
Engineering, Tianjin University, Tianjin 300072, China
- Department
of Chemical and Metallurgical Engineering, Aalto University School of Chemical Engineering, Kemistintie 1, Espoo, P.O. Box
16100, FI-00076 Aalto, Finland
| | - Y. S. Lin
- School
for Engineering of Matter, Transport and Energy, Arizona State University, Tempe, Arizona 85287, United States
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33
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Wu HC, Chen JT, Fan YH, Yen CH, Chen YM, Chang HS. Secondary metabolites from Excoecaria formosana and their anti-hepatocellular carcinoma activity. Am J Transl Res 2017. [DOI: 10.1055/s-0037-1608267] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Affiliation(s)
- HC Wu
- Graduate Institute of Natural Products, College of Pharmacy, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - JT Chen
- School of Pharmacy, College of Pharmacy, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - YH Fan
- School of Pharmacy, College of Pharmacy, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - CH Yen
- Graduate Institute of Natural Products, College of Pharmacy, Kaohsiung Medical University, Kaohsiung, Taiwan
- Center for Infectious Disease and Cancer Research (CICAR), Kaohsiung Medical University, Kaohsiung, Taiwan
| | - YM Chen
- Center for Infectious Disease and Cancer Research (CICAR), Kaohsiung Medical University, Kaohsiung, Taiwan
| | - HS Chang
- Graduate Institute of Natural Products, College of Pharmacy, Kaohsiung Medical University, Kaohsiung, Taiwan
- School of Pharmacy, College of Pharmacy, Kaohsiung Medical University, Kaohsiung, Taiwan
- Center for Infectious Disease and Cancer Research (CICAR), Kaohsiung Medical University, Kaohsiung, Taiwan
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34
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Huang HK, Cheng TL, Lin CH, Wu HC, Chen IS, Gan KH, Chang HS. Anti-Escherichia coli β-glucuronidase activity constituents from the root of Neolitsea konishii. Am J Transl Res 2017. [DOI: 10.1055/s-0037-1608150] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Affiliation(s)
- HK Huang
- School of Pharmacy, College of Pharmacy, Kaohsiung Medical University, Kaohsiung 807, Taiwan, Kaohsiung, Taiwan
| | - TL Cheng
- Department of Biomedical Science and Environmental Biology, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - CH Lin
- School of Pharmacy, College of Pharmacy, Kaohsiung Medical University, Kaohsiung 807, Taiwan, Kaohsiung, Taiwan
| | - HC Wu
- Graduate Institute of Natural Products, College of Pharmacy, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - IS Chen
- School of Pharmacy, College of Pharmacy, Kaohsiung Medical University, Kaohsiung 807, Taiwan, Kaohsiung, Taiwan
- Graduate Institute of Natural Products, College of Pharmacy, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - KH Gan
- School of Pharmacy, College of Pharmacy, Kaohsiung Medical University, Kaohsiung 807, Taiwan, Kaohsiung, Taiwan
| | - HS Chang
- School of Pharmacy, College of Pharmacy, Kaohsiung Medical University, Kaohsiung 807, Taiwan, Kaohsiung, Taiwan
- Graduate Institute of Natural Products, College of Pharmacy, Kaohsiung Medical University, Kaohsiung, Taiwan
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35
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Wu HC, Xu XP, Wu C, Lu QB, Ding ZY, Lin JF. [Spatial analysis and prediction of severe fever with thrombocytopenia syndrome in Zhejiang province, 2011-2015]. Zhonghua Liu Xing Bing Xue Za Zhi 2017; 37:1485-1490. [PMID: 28057140 DOI: 10.3760/cma.j.issn.0254-6450.2016.11.011] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Objective: To understand the distribution of the severe fever with thrombocytopenia syndrome (SFTS) in Zhejiang province, and predict the incidence and the probability of SFTS outbreak. Methods: Based on the cases of SFTS from 2011-2015, software ArcGIS 10.0 was used to analyze the spatial distribution, Moran's I and Getis-Ord Gi were used to analyze the spatial autocorrelation. The incidence trend was explored by trend surface analysis, and the prediction was made by Kriging interpolation. Results: The incidence of SFTS increased and the distribution expanded in Zhejiang from 2011 to 2015, the seasonal and the demographic characteristics of SFTS were similar to the previous research; there were regional clustering of the cases (P<0.001); a downward trend was observed from northeast to southwest in terms of incidence of SFTS; the second-order disjunctive Kriging interpolation based on circular model and the indicator Kriging interpolation based on exponential model had higher prediction accuracy, the probabilities of outbreak in Anji, Daishan and Tiantai were high, the prediction deviation of inland was less than that of edge area. Conclusion: The prediction of SFTS by Kriging interpolation had high accuracy, the incidence of SFTS was higher and the distribution of SFTS was larger than the results of surveillance, the risk areas for epidemic were Anji, Daishan, Ninghai,Tiantai, Sanmen and Linhai.
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Affiliation(s)
- H C Wu
- Zhejiang Provincial Center for Disease Control and Prevention, Hangzhou 310051, China
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36
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Zhang L, Lin BC, Wu YF, Wu HC, Huang TW, Chang CR, Ke X, Kurttepeli M, Tendeloo GV, Xu J, Yu D, Liao ZM. Electronic Coupling between Graphene and Topological Insulator Induced Anomalous Magnetotransport Properties. ACS Nano 2017; 11:6277-6285. [PMID: 28489949 DOI: 10.1021/acsnano.7b02494] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
It has been theoretically proposed that the spin textures of surface states in a topological insulator can be directly transferred to graphene by means of the proximity effect, which is very important for realizing a two-dimensional topological insulator based on graphene. Here we report the anomalous magnetotransport properties of graphene-topological insulator Bi2Se3 heterojunctions, which are sensitive to the electronic coupling between graphene and the topological surface state. The coupling between the pz orbitals of graphene and the p orbitals of the surface states on the Bi2Se3 bottom surface can be enhanced by applying a perpendicular negative magnetic field, resulting in a giant negative magnetoresistance at the Dirac point up to about -91%. An obvious resistance dip in the transfer curve at the Dirac point is also observed in the hybrid devices, which is consistent with theoretical predictions of the distorted Dirac bands with nontrivial spin textures inherited from the Bi2Se3 surface states.
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Affiliation(s)
- Liang Zhang
- State Key Laboratory for Mesoscopic Physics, School of Physics, Peking University , Beijing 100871, China
| | - Ben-Chuan Lin
- State Key Laboratory for Mesoscopic Physics, School of Physics, Peking University , Beijing 100871, China
| | - Yan-Fei Wu
- State Key Laboratory for Mesoscopic Physics, School of Physics, Peking University , Beijing 100871, China
| | - Han-Chun Wu
- School of Physics, Beijing Institute of Technology , Beijing 100081, China
| | - Tsung-Wei Huang
- Department of Physics, National Taiwan University , Taipei 10617, Taiwan
| | - Ching-Ray Chang
- Department of Physics, National Taiwan University , Taipei 10617, Taiwan
| | - Xiaoxing Ke
- Institute of Microstructures and Properties of Advanced Materials, Beijing University of Technology , Beijing 100124, China
| | - Mert Kurttepeli
- EMAT (Electron Microscopy for Materials Science), University of Antwerp , Groenenborgerlaan 171, B-2020 Antwerp, Belgium
| | - Gustaaf Van Tendeloo
- EMAT (Electron Microscopy for Materials Science), University of Antwerp , Groenenborgerlaan 171, B-2020 Antwerp, Belgium
| | - Jun Xu
- Electron Microscopy Laboratory, School of Physics, Peking University , Beijing 100871, China
| | - Dapeng Yu
- State Key Laboratory for Mesoscopic Physics, School of Physics, Peking University , Beijing 100871, China
- Department of Physics, South University of Science and Technology of China , Shenzhen 518055, China
| | - Zhi-Min Liao
- State Key Laboratory for Mesoscopic Physics, School of Physics, Peking University , Beijing 100871, China
- Collaborative Innovation Center of Quantum Matter , Beijing 100871, China
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37
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Affiliation(s)
- Han-Chun Wu
- School for Engineering of
Matter, Transport and Energy, Arizona State University, Tempe, Arizona 85287, United States
| | - Y. S. Lin
- School for Engineering of
Matter, Transport and Energy, Arizona State University, Tempe, Arizona 85287, United States
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38
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Zhuo HB, Zhang SJ, Li XH, Zhou HY, Li XZ, Zou DB, Yu MY, Wu HC, Sheng ZM, Zhou CT. Terahertz generation from laser-driven ultrafast current propagation along a wire target. Phys Rev E 2017; 95:013201. [PMID: 28208417 DOI: 10.1103/physreve.95.013201] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2016] [Indexed: 11/07/2022]
Abstract
Generation of intense coherent THz radiation by obliquely incidenting an intense laser pulse on a wire target is studied using particle-in-cell simulation. The laser-accelerated fast electrons are confined and guided along the surface of the wire, which then acts like a current-carrying line antenna and under appropriate conditions can emit electromagnetic radiation in the THz regime. For a driving laser intensity ∼3×10^{18}W/cm^{2} and pulse duration ∼10 fs, a transient current above 10 KA is produced on the wire surface. The emission-cone angle of the resulting ∼0.15 mJ (∼58 GV/m peak electric field) THz radiation is ∼30^{∘}. The conversion efficiency of laser-to-THz energy is ∼0.75%. A simple analytical model that well reproduces the simulated result is presented.
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Affiliation(s)
- H B Zhuo
- College of Science, National University of Defense Technology, Changsha 410073, People's Republic of China.,IFSA Collaborative Innovation Center, Shanghai Jiao Tong University, Shanghai 200240, People's Republic of China
| | - S J Zhang
- College of Science, National University of Defense Technology, Changsha 410073, People's Republic of China
| | - X H Li
- College of Science, National University of Defense Technology, Changsha 410073, People's Republic of China
| | - H Y Zhou
- College of Science, National University of Defense Technology, Changsha 410073, People's Republic of China
| | - X Z Li
- College of Science, National University of Defense Technology, Changsha 410073, People's Republic of China
| | - D B Zou
- College of Science, National University of Defense Technology, Changsha 410073, People's Republic of China
| | - M Y Yu
- Institute for Fusion Theory and Simulation and Department of Physics, Zhejiang University, Hangzhou 310027, People's Republic of China
| | - H C Wu
- IFSA Collaborative Innovation Center, Shanghai Jiao Tong University, Shanghai 200240, People's Republic of China.,Institute for Fusion Theory and Simulation and Department of Physics, Zhejiang University, Hangzhou 310027, People's Republic of China
| | - Z M Sheng
- IFSA Collaborative Innovation Center, Shanghai Jiao Tong University, Shanghai 200240, People's Republic of China.,SUPA, Department of Physics, University of Strathclyde, Glasgow G4 0NG, United Kingdom.,Key Laboratory for Laser Plasmas (MoE) and Department of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240, People's Republic of China
| | - C T Zhou
- College of Science, National University of Defense Technology, Changsha 410073, People's Republic of China.,Institute of Applied Physics and Computational Mathematics, Beijing 100094, People's Republic of China
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39
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Abstract
Graphene-based vertical heterostructures, particularly stacks incorporated with other layered materials, are promising for nanoelectronics. The stacking of two model Dirac materials, graphene and topological insulator, can considerably enlarge the family of van der Waals heterostructures. Despite good understanding of the two individual materials, the electron transport properties of a combined vertical heterojunction are still unknown. Here, we show the experimental realization of a vertical heterojunction between Bi2Se3 nanoplate and monolayer graphene. At low temperatures, the electron transport through the vertical heterojunction is dominated by the tunneling process, which can be effectively tuned by gate voltage to alter the density of states near the Fermi surface. In the presence of a magnetic field, quantum oscillations are observed due to the quantized Landau levels in both graphene and the two-dimensional surface states of Bi2Se3. Furthermore, we observe an exotic gate-tunable tunneling resistance under high magnetic field, which displays resistance maxima when the underlying graphene becomes a quantum Hall insulator.
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Affiliation(s)
- Liang Zhang
- State Key Laboratory for Mesoscopic Physics, School of Physics, Peking University , Beijing 100871, P.R. China
| | - Yuan Yan
- State Key Laboratory for Mesoscopic Physics, School of Physics, Peking University , Beijing 100871, P.R. China
| | - Han-Chun Wu
- School of Physics, Beijing Institute of Technology , Beijing 100081, P.R. China
| | - Dapeng Yu
- State Key Laboratory for Mesoscopic Physics, School of Physics, Peking University , Beijing 100871, P.R. China
- Collaborative Innovation Center of Quantum Matter , Beijing 100871, China
- Electron Microscopy Laboratory, School of Physics, Peking University , Beijing 100871, P.R. China
| | - Zhi-Min Liao
- State Key Laboratory for Mesoscopic Physics, School of Physics, Peking University , Beijing 100871, P.R. China
- Collaborative Innovation Center of Quantum Matter , Beijing 100871, China
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40
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Krishna Murthy J, Chandrasekhar KD, Wu HC, Yang HD, Lin JY, Venimadhav A. Antisite disorder driven spontaneous exchange bias effect in La(2-x)Sr(x) CoMnO₆ (0 ⩽ x ⩽ 1). J Phys Condens Matter 2016; 28:086003. [PMID: 26823459 DOI: 10.1088/0953-8984/28/8/086003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Doping at the rare-earth site by divalent alkaline-earth ions in perovskite lattice has witnessed a variety of magnetic and electronic orders with spatially correlated charge, spin and orbital degrees of freedom. Here, we report an antisite disorder driven spontaneous exchange bias effect as a result of hole carrier (Sr(2+)) doping in La(2-x)Sr(x)CoMnO6 (0 < x < 1) double perovskites. X-ray diffraction and Raman spectroscopy have evidenced an increase in disorder with the increase of Sr content up to x = 0.5 and thereby a decrease from x = 0.5 to 1. X-ray absorption spectroscopy has revealed that only Co is present in the mixed valence of Co(2+) and Co(3+) states with Sr doping to compensate the charge neutrality. Magnetotransport is strongly correlated with the increase of antisite disorder. The antisite disorder at the B-site interrupts the long-range ferromagnetic order by introducing various magnetic interactions and instigates reentrant glassy dynamics, phase separation and canted type antiferromagnetic behavior with the decrease of temperature. This leads to a novel magnetic microstructure with unidirectional anisotropy that causes a spontaneous exchange bias effect that can be tuned with the amount of antisite disorder.
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Affiliation(s)
- J Krishna Murthy
- Cryogenic Engineering Centre, Indian Institute of Technology, Kharagpur-721302, India
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41
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Zhang D, Wu YC, Yang M, Liu X, Coileáin CÓ, Xu H, Abid M, Abid M, Wang JJ, Shvets IV, Liu H, Wang Z, Yin H, Liu H, Chun BS, Zhang X, Wu HC. Probing thermal expansion coefficients of monolayers using surface enhanced Raman scattering. RSC Adv 2016. [DOI: 10.1039/c6ra20623a] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
A non-destructive method has been proposed to probe thermal expansion coefficients of the monolayer materials using surface-enhanced Raman spectroscopy.
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42
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Wang LX, Yan Y, Zhang L, Liao ZM, Wu HC, Yu DP. Zeeman effect on surface electron transport in topological insulator Bi2Se3 nanoribbons. Nanoscale 2015; 7:16687-16694. [PMID: 26400635 DOI: 10.1039/c5nr05250e] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Topological insulators have exotic surface states that are massless Dirac fermions, manifesting special magnetotransport properties, such as the Aharonov-Bohm effect, Shubnikov-de Haas oscillations, and weak antilocalization effects. In the surface Dirac cone, the band structures are typically closely related to the p-orbitals and possess helical orbital texture. Here we report on the tunability of the transport properties via the interaction between the magnetic field and the spin-orbital angular momentum of the surface states in individual Bi2Se3 nanoribbons. Because the surface states have a large Landé factor and helical spin-orbital texture, the in-plane magnetic field induced Zeeman energy will result in the deformation of the Dirac cone, which gives rise to spin polarization of the surface states. The spin-dependent scattering of the conducting electrons on the existing local magnetic moments produces a giant negative magnetoresistance. The negative magnetoresistance is robust with a ratio of -20% at 2 K and -0.5% at 300 K under 14 T. The results are valuable for possible orbital-electronics based on topological insulators.
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Affiliation(s)
- Li-Xian Wang
- State Key Laboratory for Mesoscopic Physics, Department of Physics, Peking University, Beijing 100871, P. R. China.
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43
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Wu HC, Chaika AN, Huang TW, Syrlybekov A, Abid M, Aristov VY, Molodtsova OV, Babenkov SV, Marchenko D, Sánchez-Barriga J, Mandal PS, Varykhalov AY, Niu Y, Murphy BE, Krasnikov SA, Lübben O, Wang JJ, Liu H, Yang L, Zhang H, Abid M, Janabi YT, Molotkov SN, Chang CR, Shvets I. Transport Gap Opening and High On-Off Current Ratio in Trilayer Graphene with Self-Aligned Nanodomain Boundaries. ACS Nano 2015; 9:8967-8975. [PMID: 26302083 DOI: 10.1021/acsnano.5b02877] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Trilayer graphene exhibits exceptional electronic properties that are of interest both for fundamental science and for technological applications. The ability to achieve a high on-off current ratio is the central question in this field. Here, we propose a simple method to achieve a current on-off ratio of 10(4) by opening a transport gap in Bernal-stacked trilayer graphene. We synthesized Bernal-stacked trilayer graphene with self-aligned periodic nanodomain boundaries (NBs) on the technologically relevant vicinal cubic-SiC(001) substrate and performed electrical measurements. Our low-temperature transport measurements clearly demonstrate that the self-aligned periodic NBs can induce a charge transport gap greater than 1.3 eV. More remarkably, the transport gap of ∼0.4 eV persists even at 100 K. Our results show the feasibility of creating new electronic nanostructures with high on-off current ratios using graphene on cubic-SiC.
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Affiliation(s)
- Han-Chun Wu
- School of Physics, Beijing Institute of Technology , Beijing 100081, People's Republic of China
| | - Alexander N Chaika
- CRANN, School of Physics, Trinity College Dublin , Dublin 2, Ireland
- Institute of Solid State Physics, Russian Academy of Sciences , Chernogolovka, Moscow District 142432, Russian Federation
| | - Tsung-Wei Huang
- Department of Physics, National Taiwan University , Taipei 10617, Taiwan
| | - Askar Syrlybekov
- CRANN, School of Physics, Trinity College Dublin , Dublin 2, Ireland
| | - Mourad Abid
- KSU-Aramco Center, King Saud University , Riyadh 11451, Saudi Arabia
| | - Victor Yu Aristov
- Institute of Solid State Physics, Russian Academy of Sciences , Chernogolovka, Moscow District 142432, Russian Federation
- HASYLAB at DESY , D-22607 Hamburg, Germany
- Institut für Theoretische Physik, Universität Hamburg , Jungiusstrasse 9, D-20355 Hamburg, Germany
| | | | | | - D Marchenko
- Helmholtz-Zentrum Berlin für Materialien und Energie , D-12489 Berlin, Germany
- Freie Universität Berlin , D-14195 Berlin, Germany
| | | | | | | | - Yuran Niu
- MAX-lab, Lund University , Box 118, 22100 Lund, Sweden
| | - Barry E Murphy
- CRANN, School of Physics, Trinity College Dublin , Dublin 2, Ireland
| | | | - Olaf Lübben
- CRANN, School of Physics, Trinity College Dublin , Dublin 2, Ireland
| | - Jing Jing Wang
- CRANN, School of Physics, Trinity College Dublin , Dublin 2, Ireland
| | - Huajun Liu
- Institute of Plasma Physics, Chinese Academy of Sciences , Hefei 230031, People's Republic of China
| | - Li Yang
- Electronic Engineering Institute , Hefei 230037, People's Republic of China
| | - Hongzhou Zhang
- CRANN, School of Physics, Trinity College Dublin , Dublin 2, Ireland
| | - Mohamed Abid
- KSU-Aramco Center, King Saud University , Riyadh 11451, Saudi Arabia
| | - Yahya T Janabi
- Saudi Aramco Materials Performance Unit TSD, Research & Development Center, Dharhan 31311, Saudi Arabia
| | - Sergei N Molotkov
- Institute of Solid State Physics, Russian Academy of Sciences , Chernogolovka, Moscow District 142432, Russian Federation
| | - Ching-Ray Chang
- Department of Physics, National Taiwan University , Taipei 10617, Taiwan
| | - Igor Shvets
- CRANN, School of Physics, Trinity College Dublin , Dublin 2, Ireland
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44
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Syrlybekov A, Wu HC, Mauit O, Wu YC, Maguire P, Khalid A, Coileáin CÓ, Farrell L, Heng CL, Abid M, Liu H, Yang L, Zhang HZ, Shvets IV. Electrical-field-driven metal-insulator transition tuned with self-aligned atomic defects. Nanoscale 2015; 7:14055-14061. [PMID: 26239065 DOI: 10.1039/c5nr03251b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Recently, significant attention has been paid to the resistance switching (RS) behaviour in Fe3O4 and it was explained through the analogy of the electrically driven metal-insulator transition based on the quantum tunneling theory. Here, we propose a method to experimentally support this explanation and provide a way to tune the critical switching parameter by introducing self-aligned localized impurities through the growth of Fe3O4 thin films on stepped SrTiO3 substrates. Anisotropic behavior in the RS was observed, where a lower switching voltage in the range of 10(4) V cm(-1) is required to switch Fe3O4 from a high conducting state to a low conducting state when the electrical field is applied along the steps. The anisotropic RS behavior is attributed to a high density array of anti-phase boundaries (APBs) formed at the step edges and thus are aligned along the same direction in the film which act as a train of hotspot forming conduits for resonant tunneling. Our experimental studies open an interesting window to tune the electrical-field-driven metal-insulator transition in strongly correlated systems.
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Affiliation(s)
- Askar Syrlybekov
- School of Physics, Beijing Institute of Technology, Beijing 100081, People's Republic of China.
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45
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Fox DS, Zhou Y, Maguire P, O'Neill A, Ó'Coileáin C, Gatensby R, Glushenkov AM, Tao T, Duesberg GS, Shvets IV, Abid M, Abid M, Wu HC, Chen Y, Coleman JN, Donegan JF, Zhang H. Nanopatterning and Electrical Tuning of MoS2 Layers with a Subnanometer Helium Ion Beam. Nano Lett 2015; 15:5307-13. [PMID: 26154305 DOI: 10.1021/acs.nanolett.5b01673] [Citation(s) in RCA: 87] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
We report subnanometer modification enabled by an ultrafine helium ion beam. By adjusting ion dose and the beam profile, structural defects were controllably introduced in a few-layer molybdenum disulfide (MoS2) sample and its stoichiometry was modified by preferential sputtering of sulfur at a few-nanometer scale. Localized tuning of the resistivity of MoS2 was demonstrated and semiconducting, metallic-like, or insulating material was obtained by irradiation with different doses of He(+). Amorphous MoSx with metallic behavior has been demonstrated for the first time. Fabrication of MoS2 nanostructures with 7 nm dimensions and pristine crystal structure was also achieved. The damage at the edges of these nanostructures was typically confined to within 1 nm. Nanoribbons with widths as small as 1 nm were reproducibly fabricated. This nanoscale modification technique is a generalized approach that can be applied to various two-dimensional (2D) materials to produce a new range of 2D metamaterials.
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Affiliation(s)
| | | | | | | | | | | | - Alexey M Glushenkov
- §Institute for Frontier Materials, Deakin University, Waurn Ponds, VIC 3216, Australia
- ∥Melbourne Centre for Nanofabrication, 151 Wellington Rd, Clayton, VIC 3168, Australia
| | - Tao Tao
- §Institute for Frontier Materials, Deakin University, Waurn Ponds, VIC 3216, Australia
| | | | | | - Mohamed Abid
- ⊥KSU-Aramco Center, King Saud University, Riyadh 11451, Saudi Arabia
| | - Mourad Abid
- ⊥KSU-Aramco Center, King Saud University, Riyadh 11451, Saudi Arabia
| | - Han-Chun Wu
- #School of Physics, Beijing Institute of Technology, Beijing, 100081, People's Republic of China
| | - Ying Chen
- §Institute for Frontier Materials, Deakin University, Waurn Ponds, VIC 3216, Australia
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46
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Wu HC, Abid M, Wu YC, Coileáin CÓ, Syrlybekov A, Han JF, Heng CL, Liu H, Abid M, Shvets I. Enhanced Shubnikov-De Haas Oscillation in Nitrogen-Doped Graphene. ACS Nano 2015; 9:7207-7214. [PMID: 26061979 DOI: 10.1021/acsnano.5b02020] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
N-doped graphene displays many interesting properties compared with pristine graphene, which makes it a potential candidate in many applications. Here, we report that the Shubnikov-de Haas (SdH) oscillation effect in graphene can be enhanced by N-doping. We show that the amplitude of the SdH oscillation increases with N-doping and reaches around 5k Ω under a field of 14 T at 10 K for highly N-doped graphene, which is over 1 order of magnitude larger than the value found for pristine graphene devices with the same geometry. Moreover, in contrast to the well-established standard Lifshitz-Kosevich theory, the amplitude of the SdH oscillation decreases linearly with increasing temperature and persists up to a temperature of 150 K. Our results also show that the magnetoresistance (MR) in N-doped graphene increases with increasing temperature. Our results may be useful for the application of N-doped graphene in magnetic devices.
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Affiliation(s)
- Han-Chun Wu
- †School of Physics, Beijing Institute of Technology, Beijing 100081, People's Republic of China
| | - Mourad Abid
- ‡KSU-Aramco Center, King Saud University, Riyadh 11451, Saudi Arabia
| | - Ye-Cun Wu
- †School of Physics, Beijing Institute of Technology, Beijing 100081, People's Republic of China
| | - Cormac Ó Coileáin
- †School of Physics, Beijing Institute of Technology, Beijing 100081, People's Republic of China
- §CRANN, School of Physics, Trinity College, University of Dublin, Dublin 2, Ireland
| | - Askar Syrlybekov
- §CRANN, School of Physics, Trinity College, University of Dublin, Dublin 2, Ireland
| | - Jun Feng Han
- †School of Physics, Beijing Institute of Technology, Beijing 100081, People's Republic of China
| | - Cheng Lin Heng
- †School of Physics, Beijing Institute of Technology, Beijing 100081, People's Republic of China
| | - Huajun Liu
- ⊥Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031, People's Republic of China
| | - Mohamed Abid
- ‡KSU-Aramco Center, King Saud University, Riyadh 11451, Saudi Arabia
| | - Igor Shvets
- §CRANN, School of Physics, Trinity College, University of Dublin, Dublin 2, Ireland
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47
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Wu HC, Mauit O, Coileáin CÓ, Syrlybekov A, Khalid A, Mouti A, Abid M, Zhang HZ, Abid M, Shvets IV. Magnetic and transport properties of epitaxial thin film MgFe2O4 grown on MgO (100) by molecular beam epitaxy. Sci Rep 2014; 4:7012. [PMID: 25388355 PMCID: PMC4228329 DOI: 10.1038/srep07012] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [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: 07/29/2014] [Accepted: 10/13/2014] [Indexed: 11/09/2022] Open
Abstract
Magnesium ferrite is a very important magnetic material due to its interesting magnetic and electrical properties and its chemical and thermal stability. Here we report on the magnetic and transport properties of epitaxial MgFe2O4 thin films grown on MgO (001) by molecular beam epitaxy. The structural properties and chemical composition of the MgFe2O4 films were characterized by X-Ray diffraction and X-Ray photoelectron spectroscopy, respectively. The nonsaturation of the magnetization in high magnetic fields observed for M (H) measurements and the linear negative magnetoresistance (MR) curves indicate the presence of anti-phase boundaries (APBs) in MgFe2O4. The presence of APBs was confirmed by transmission electron microscopy. Moreover, post annealing decreases the resistance and enhances the MR of the film, suggesting migration of the APBs. Our results may be valuable for the application of MgFe2O4 in spintronics.
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Affiliation(s)
- Han-Chun Wu
- 1] School of Physics, Beijing Institute of Technology, Beijing, 100081, P. R. China [2] KSU-Aramco Center, King Saud University, Riyadh 11451, Saudi Arabia
| | - Ozhet Mauit
- CRANN, School of Physics, Trinity College, Dublin 2, Ireland
| | - Cormac Ó Coileáin
- 1] KSU-Aramco Center, King Saud University, Riyadh 11451, Saudi Arabia [2] CRANN, School of Physics, Trinity College, Dublin 2, Ireland
| | | | - Abbas Khalid
- CRANN, School of Physics, Trinity College, Dublin 2, Ireland
| | - Anas Mouti
- KSU-Aramco Center, King Saud University, Riyadh 11451, Saudi Arabia
| | - Mourad Abid
- KSU-Aramco Center, King Saud University, Riyadh 11451, Saudi Arabia
| | - Hong-Zhou Zhang
- CRANN, School of Physics, Trinity College, Dublin 2, Ireland
| | - Mohamed Abid
- KSU-Aramco Center, King Saud University, Riyadh 11451, Saudi Arabia
| | - Igor V Shvets
- CRANN, School of Physics, Trinity College, Dublin 2, Ireland
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48
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Yan Y, Liao ZM, Ke X, Van Tendeloo G, Wang Q, Sun D, Yao W, Zhou S, Zhang L, Wu HC, Yu DP. Topological surface state enhanced photothermoelectric effect in Bi2Se3 nanoribbons. Nano Lett 2014; 14:4389-94. [PMID: 25046135 DOI: 10.1021/nl501276e] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
The photothermoelectric effect in topological insulator Bi2Se3 nanoribbons is studied. The topological surface states are excited to be spin-polarized by circularly polarized light. Because the direction of the electron spin is locked to its momentum for the spin-helical surface states, the photothermoelectric effect is significantly enhanced as the oriented motions of the polarized spins are accelerated by the temperature gradient. The results are explained based on the microscopic mechanisms of a photon induced spin transition from the surface Dirac cone to the bulk conduction band. The as-reported enhanced photothermoelectric effect is expected to have potential applications in a spin-polarized power source.
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Affiliation(s)
- Yuan Yan
- State Key Laboratory for Mesoscopic Physics, Department of Physics and ∥International Center for Quantum Materials, Peking University , Beijing 100871, P. R. China
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Abstract
Vacancies can induce local magnetic moments in graphene, paving the way to make magnetic functional graphene. Due to the interaction between magnetic moments and conduction carriers, the magnetotransport properties of graphene can be modulated. Here, the effects of vacancy induced magnetic moments on the electrical properties of graphene are studied via magnetotransport measurements and spin-polarized density functional theory calculations. We show by quantum Hall measurements that a sharp resonant Vπ state is introduced in the midgap region of graphene with vacancies, resulting in the local magnetic moment. The coupling between the localized Vπ state and the itinerant carrier is tuned by varying the carrier concentration, temperature, magnetic field, and vacancy density, which results in a transition between hopping transport and the Kondo effect and a transition between giant negative magnetoresistance (MR) and positive MR. This modulated magnetotransport is valuable for graphene based spintronic devices.
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Affiliation(s)
- Jing-Jing Chen
- State Key Laboratory for Mesoscopic Physics, Department of Physics, Peking University, Beijing 100871, P.R. China.
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Song Y, Wu HC. Ballistic collective group delay and its Goos-Hänchen component in graphene. J Phys Condens Matter 2013; 25:355301. [PMID: 23911969 DOI: 10.1088/0953-8984/25/35/355301] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
We theoretically construct an experimental observable for the ballistic collective group delay (CGD) of all the particles on the Fermi surface in graphene. First, we reveal that lateral Goos-Hänchen (GH) shifts along barrier interfaces contribute an inherent component in the individual group delay (IGD). Then, by linking the complete IGD to spin precession through a dwell time, we suggest that the CGD and its GH component can be electrostatically measured by the conductance difference in a spin precession experiment under weak magnetic fields. Such an approach is feasible for almost any Fermi energy. We also indicate that it is a generally nonzero self-interference delay that relates the IGD to the dwell time in graphene.
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Affiliation(s)
- Yu Song
- Department of Physics and State Key Laboratory of Low-Dimensional Quantum Physics, Tsinghua University, Beijing 100084, People's Republic of China.
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