Article
Chemistry, Multidisciplinary
Xiaoqing Chen, Yu Zhang, Ruijuan Tian, Xianghu Wu, Zhengdong Luo, Yan Liu, Xinran Wang, Jianlin Zhao, Xuetao Gan
Summary: A quadratically nonlinear photodetector (QNPD) composed of a van der Waals (vdW) stacked GaSe/InSe heterostructure is reported in this study. The QNPD exhibits unique electronic and optical attributes and extends the photodetection wavelength range from 900 to 1750 nm due to the extra second-harmonic generation (SHG) process in GaSe/InSe. It is highly sensitive to the variation of optical intensity and can be used as an autocorrelator for measuring ultrafast pulse widths and an optoelectronic mixer for signal processing.
Article
Chemistry, Physical
Luji Li, Gaojie Zhang, Hao Wu, Li Yang, Pengfei Gao, Shanfei Zhang, Xiaokun Wen, Wenfeng Zhang, Haixin Chang
Summary: Weyl semimetal WTe2/MoS2 van der Waals heterojunctions, with the incorporation of MoS2, demonstrate stable photoresponse from visible light to near-infrared, showing tunable photocurrent and faster response compared to pristine MoS2. This study highlights the great potential of WTe2 and other topological semimetals in photodetectors.
JOURNAL OF PHYSICAL CHEMISTRY C
(2021)
Article
Materials Science, Multidisciplinary
Zihao Liu, Kaixiang Shu, Yujue Yang, He Yu, Ying Huang, Wei Gao, Xin Zhang, Fugen Wu, Jingbo Li, Huafeng Dong, Nengjie Huo
Summary: Van der Waals (vdW) heterojunction with integrated graphene shows superior power-conversion-efficiency (PCE) and photodetection performance, greatly improving the photovoltaic effect and energy-harvesting potential. The graphene acts as electron and hole transport layers, increasing the collection efficiency of photo-excited carriers. This work provides a universal approach for highly efficient energy-harvesting and photodetector applications.
ADVANCED OPTICAL MATERIALS
(2023)
Article
Chemistry, Physical
Shuo Li, Qiang Wu, Haokun Ding, Songsong Wu, Xinwei Cai, Rui Wang, Jun Xiong, Guangyang Lin, Wei Huang, Songyan Chen, Cheng Li
Summary: In this study, a p-WSe2/n-Ge vdW heterojunction phototransistor with a Schottky barrier collector on n-Ge for broadband photodetection is reported. The phototransistor exhibits high responsivities, photocurrent gain, and fast response time, making it suitable for high-performance broadband photodetection.
Article
Chemistry, Physical
Ick-Joon Park, Tae In Kim
Summary: In this study, the superior properties of two-dimensional van der Waals heterojunctions and their potential for enhanced optoelectronic devices are demonstrated. The band alignment at the MoS2/GO heterojunction is investigated, revealing a type II band alignment. It is found that the band alignment can be controlled by modifying the thickness of MoS2 and the degree of reduction in GO. This research provides valuable insights for the development of next-generation optoelectronic applications.
JOURNAL OF ALLOYS AND COMPOUNDS
(2023)
Article
Chemistry, Physical
Huawei Liu, Lizhen Fang, Xiaoli Zhu, Chenguang Zhu, Xingxia Sun, Gengzhao Xu, Biyuan Zheng, Ying Liu, Ziyu Luo, Hui Wang, Chengdong Yao, Dong Li, Anlian Pan
Summary: A novel contact strategy using Bi2Te3 nanosheets as van der Waals contacts on MoS2 is proposed in this study to address the poor contact quality issue in two-dimensional semiconductor-based field effect transistors (FETs). The results show that the MoS2 FET device with Bi2Te3 contacts exhibits higher performance and smaller Schottky barrier height.
Article
Materials Science, Multidisciplinary
Xinwei Cai, Shuo Li, Jinhui Qian, Haokun Ding, Songsong Wu, Rui Wang, Qiang Wu, Xiaowei Shentu, Guangyang Lin, Cheng Li
Summary: In this work, a high-performance two-terminal n-MoSe2/p-GeSn/n-Ge van der Waals heterojunction phototransistor (HPT) is proposed and demonstrated for short-wave infrared (SWIR) detection. The device exhibits a high responsivity and specific detectivity, making it a promising candidate for infrared detection above 2 μm.
ADVANCED OPTICAL MATERIALS
(2023)
Article
Chemistry, Multidisciplinary
Zongqi Bai, Yang Xiao, Qing Luo, Miaomiao Li, Gang Peng, Zhihong Zhu, Fang Luo, Mengjian Zhu, Shiqiao Qin, Kostya Novoselov
Summary: The emergence of two-dimensional materials has led to important applications in electronic and optoelectronic devices. However, there are limitations such as low ON/OFF ratio and Schottky barrier formation. In this study, highly tunable field-effect tunneling transistors based on vertical graphene-WS2-graphene heterostructures were demonstrated, overcoming these limitations and achieving low off-state current, high ON/OFF ratio, and controllable carrier transport polarity.
Article
Nanoscience & Nanotechnology
Wen Jin, Gaojie Zhang, Hao Wu, Li Yang, Wenfeng Zhang, Haixin Chang
Summary: This study demonstrates a room-temperature magnetic tunnel junction (MTJ) based on a Fe3GaTe2/WS2/Fe3GaTe2 heterostructure, which exhibits a tunneling magnetoresistance (TMR) ratio of up to 213% and a high spin polarization of 72% at 10 K, the highest reported in Fe3GaTe2-based MTJs so far. The MTJ also maintains a robust tunneling spin-valve signal at room temperature (300 K) with low bias currents, offers potential for low-energy consumption in all-2D vdW spintronics and provides alternative routes for electronic control of spintronic devices.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Chemistry, Multidisciplinary
Zhouxiaosong Zeng, Cuihuan Ge, Kai Braun, Martin Eberle, Yufan Wang, Biyuan Zheng, Chenguang Zhu, Xingxia Sun, Lanyu Huang, Ziyu Luo, Ying Chen, Huigao Duan, Shuangyin Wang, Dong Li, Fei Gao, Anlian Pan, Xiao Wang
Summary: In this study, van der Waals heterostructure photodetectors based on MoS2/WSe2 p-n and n-n junctions were constructed and the picosecond photoresponse was manipulated by combining photovoltaic and photothermoelectric effects. The experiments showed that a TRPC peak at zero time delay was observed in the n-n junction device with a short decay time, while a TRPC dip was observed in the p-n junction and pure WSe2 devices, indicating opposite current polarities between PV and PTE. By modulating the ultrafast photocurrent, a transition from a peak to a dip was realized, and detailed carrier transport dynamics were analyzed.
ADVANCED FUNCTIONAL MATERIALS
(2022)
Article
Materials Science, Multidisciplinary
Shaofeng Zhang, Zhaowu Wang
Summary: The contact type between graphene and semiconducting two-dimensional materials plays a crucial role in nanoscale electronic devices. In this study, the contact type between graphene and SiCP4 is investigated, and it is found that the Schottky barrier can be tuned by changing the interlayer distance. The charge transfer at the interface explains the change in the Schottky barrier, and applying a vertical electric field can further control it. This tunable Schottky barrier provides guidance for the design of nanodevices based on graphene and SiCP4.
RESULTS IN PHYSICS
(2023)
Article
Chemistry, Multidisciplinary
Duan Luo, Jian Tang, Xiaozhe Shen, Fuhao Ji, Jie Yang, Stephen Weathersby, Michael E. Kozina, Zhijiang Chen, Jun Xiao, Yusen Ye, Ting Cao, Guangyu Zhang, Xijie Wang, Aaron M. Lindenberg
Summary: The study utilized ultrafast electron diffraction to simultaneously visualize charge transfer and electron-phonon coupling in MoS2-graphene heterostructures. It was found that the timescale of charge transfer and relaxation varies significantly with twist angle, indicating that twist angle can serve as an additional tuning knob for interlayer charge transfer in heterobilayers. The research deepened the understanding of fundamental photophysical processes in heterostructures, which is important for future applications in optoelectronics and light harvesting.
Article
Physics, Applied
Jiazhong Shen, Huaizhong Xing, Lin Wang, Zhen Hu, Libo Zhang, Xueyan Wang, Zhiqingzi Chen, Chenyu Yao, Mengjie Jiang, Fucong Fei, Gang Chen, Li Han, Fengqi Song, Xiaoshuang Chen
Summary: In this work, a terahertz detector based on a NiTe2-graphene van der Waals heterostructure has been developed to inhibit dark current and thermal-agitation noise at room temperature. The device exhibits enhanced photon-absorption ability and conversion of terahertz radiation into a direct current, achieving high photoresponsivity and low noise equivalent power.
APPLIED PHYSICS LETTERS
(2022)
Article
Chemistry, Analytical
Do-Hyun Park, Hyo Chan Lee
Summary: The development of short-wave infrared photodetectors based on different 2D materials operating at room temperature has attracted attention. Van der Waals heterostructures of 2D materials with type-II band alignment have potential for use in photodetectors, but high photoresponsivity is essential. In this study, we investigated the photogating of graphene using a monolayer-MoS2/monolayer-MoTe2 van der Waals heterostructure. By stacking MoS2/MoTe2 on graphene, a broadband photodetector with high photoresponsivity (>100 mA/W) and low dark current (60 nA) across a wide wavelength range (488-1550 nm) was fabricated.
Article
Materials Science, Multidisciplinary
S. Hu, S. Ju, C. Shao, J. Guo, B. Xu, M. Ohnishi, J. Shiomi
Summary: Efforts to control thermal transport via coherent phonons in one-dimensional superlattices are on the rise. By studying phonon transport in vdW graphene-MoS2 heterostructures, the optimal stacking order was identified leading to significantly lower thermal conductivity. The physical mechanism of coherent phonon localization was uncovered, providing insights for further development in phononics.
MATERIALS TODAY PHYSICS
(2021)
Article
Optics
Junling Qu, Mateusz Weis, Eva Izquierdo, Simon Gwenael Mizrahi, Audrey Chu, Corentin Dabard, Charlie Greboval, Erwan Bossavit, Yoann Prado, Emmanuel Peronne, Sandrine Ithurria, Gilles Patriarche, Mathieu G. Silly, Gregory Vincent, Davide Boschetto, Emmanuel Lhuillier
Summary: This paper reports the design of a HgTe nanocrystal-based LED with emission between 2 and 2.3 mu m, showing competitive performance with an external quantum efficiency of 0.3% and radiance up to 3 W Sr-1 m(-2) for wavelengths above 2 mu m.
Article
Materials Science, Multidisciplinary
Erwan Bossavit, Junling Qu, Claire Abadie, Corentin Dabard, Tung Dang, Eva Izquierdo, Adrien Khalili, Charlie Greboval, Audrey Chu, Stefano Pierini, Mariarosa Cavallo, Yoann Prado, Victor Parahyba, Xiang Zhen Xu, Armel Decamps-Mandine, Mathieu Silly, Sandrine Ithurria, Emmanuel Lhuillier
Summary: Nanocrystals have been successfully integrated into optoelectronic devices, with the next challenge being the combination of multiple devices into a complex system for better on-chip integration. In this study, the focus is on an all-HgTe-NC active imaging setup in the short-wave infrared range. By optimizing the design of an IR LED and imaging the IR emission using a focal plane array, significant progress has been made towards all-NC-based active imaging setups.
ADVANCED OPTICAL MATERIALS
(2022)
Article
Nanoscience & Nanotechnology
Charlie Greboval, Eva Izquierdo, Claire Abadie, Adrien Khalili, Mariarosa Cavallo, Audrey Chu, Tung Huu Dang, Huichen Zhang, Xavier Lafosse, Michael Rosticher, Xiang Zhen Xu, Armel Descamps-Mandine, Abdelkarim Ouerghi, Mathieu G. Silly, Sandrine Ithurria, Emmanuel Lhuillier
Summary: This study investigates the application of HgTe nanocrystals (NCs) in photodiodes using a SnO2/HgTe/Ag2Te structure. By optimizing the band alignment, the SnO2 layer filters out hole dark current while allowing photogenerated electrons to flow, resulting in enhanced rectifying behavior and high internal efficiency. The study also addresses the challenge of transferring the diode onto readout circuits and demonstrates the reversibility of the diode stack with a partially transparent conducting electrode on the top, maintaining device responsivity. Additionally, the SnO2 layer benefits electron injection and enhances electroluminescence signals.
ACS APPLIED NANO MATERIALS
(2022)
Article
Chemistry, Physical
Djawhar Ferrah, Jose Penuelas, Frederic Boudaa, Claude Botella, Mathieu Silly, Fausto Sirotti, Genevieve Grenet
Summary: In this paper, the key factors affecting the initial stages of growing nanowires by vapor-liquid-solid mechanism using gold as catalyst, including surface preparation of the silicon wafer, gold deposition, and subsequent annealing, were investigated. The results showed that gold deposited on clean Si formed a AuSi alloy at the surface, while on SiO2-covered Si, gold slightly sunk into the silica. During annealing, gold gradually sunk into the silica, catalyzing its decomposition. This resulted in local changes in surface potential and the eventual mixing of gold and silicon. These findings provide new insights into the vapor-liquid-solid mechanism and its role in nanowire growth.
JOURNAL OF PHYSICAL CHEMISTRY C
(2022)
Article
Nanoscience & Nanotechnology
Lama Khalil, Debora Pierucci, Emilio Velez-Fort, Jose Avila, Celine Vergnaud, Pavel Dudin, Fabrice Oehler, Julien Chaste, Matthieu Jamet, Emmanuel Lhuillier, Marco Pala, Abdelkarim Ouerghi
Summary: This study visualizes the presence of a flat band near the Fermi level in the van der Waals WSe2/MoSe2 heterobilayer and confirms the coexistence of different domains with arbitrary twist angles. The strong interlayer hybridization effects are observed, which are further confirmed by complementary micro-Raman spectroscopy measurements.
Article
Chemistry, Multidisciplinary
Mariarosa Cavallo, Erwan Bossavit, Huichen Zhang, Corentin Dabard, Tung Huu Dang, Adrien Khalili, Claire Abadie, Rodolphe Alchaar, Dario Mastrippolito, Yoann Prado, Loic Becerra, Michael Rosticher, Mathieu G. Silly, James K. Utterback, Sandrine Ithurria, Jose Avila, Debora Pierucci, Emmanuel Lhuillier
Summary: As nanocrystal-based optoelectronics advances, there is a need for advanced techniques to reveal the electronic structure of nanocrystals, especially under device-relevant conditions. Previous efforts have mainly focused on optical spectroscopy and electrochemistry, which require an absolute energy reference. In this study, we explored the use of photoemission microscopy as a strategy for investigating nanocrystal-based devices in real-time. The method was found to be applicable to different materials and device geometries, providing direct access to important information such as metal-semiconductor interface band bending and gate effect propagation distance.
Article
Nanoscience & Nanotechnology
Jihene Zribi, Debora Pierucci, Federico Bisti, Biyuan Zheng, Jose Avila, Lama Khalil, Cyrine Ernandes, Julien Chaste, Fabrice Oehler, Marco Pala, Thomas Maroutian, Ilka Hermes, Emmanuel Lhuillier, Anlian Pan, Abdelkarim Ouerghi
Summary: By characterizing the electronic properties of a single layer WS1.4Se0.6 alloy, researchers have discovered its unique anisotropic properties. The alloy exhibits a giant unidirectional Rashba spin splitting and in-plane polarization, which could have wide-ranging applications in future electronic, piezoelectric, and spintronic devices.
Article
Nanoscience & Nanotechnology
Huichen Zhang, Victor Guilloux, Erwan Bossavit, Ningyuan Fu, Corentin Dabard, Mariarosa Cavallo, Tung Huu Dang, Adrien Khalili, Claire Abadie, Rodolphe Alchaar, Charlie Greboval, Xiang Zhen Xu, James K. Utterback, Debora Pierucci, Sandrine Ithurria, Juan I. Climente, Thierry Barisien, Emmanuel Lhuillier
Summary: In this study, we designed light amplitude modulators based on nanocrystal-based light-emitting diodes operated under reverse bias, achieving strong photoluminescence modulations for visible and near-telecom wavelengths using low bias operations (< 3 V) compatible with conventional electronics. For a visible device, we demonstrated that the photoluminescence quenching is driven by the field-induced change of nonradiative decay rate, and that the role of the field is less involved than the particle charging. This work shows that a simple diode stack can combine multiple functionalities (light-emitting diode, detector, and light modulator) simply by selecting the driving bias.
Article
Multidisciplinary Sciences
Qicheng Zhang, Li He, Eugene J. Mele, Bo Zhen, A. T. Charlie Johnson
Summary: Integrated phononics plays a crucial role in fundamental physics and technology. This study investigates the use of piezomagnetic materials to break time-reversal symmetry and achieve topological phases and non-reciprocal devices. The authors develop a theoretical framework that combines linear elasticity with Maxwell's equations and demonstrate the existence of phononic Chern insulators based on piezomagnetism.
NATURE COMMUNICATIONS
(2023)
Article
Nanoscience & Nanotechnology
Tung Huu Dang, Claire Abadie, Audrey Chu, Mariarosa Cavallo, Adrien Khalili, Corentin Dabard, Erwan Bossavit, Huichen Zhang, Yoann Prado, Debora Pierucci, James K. Utterback, Yanko Todorov, Carlo Sirtori, Julien Jaeck, Gregory Vincent, Angela Vasanelli, Baptiste Fix, Emmanuel Lhuillier
Summary: The coupling of a photonic structure to a nanocrystal film allows for remote light focusing compatible with the charge diffusion length. This strategy has been applied in infrared sensors to enhance absorption. Additionally, the photonic structure can be used to generate a bias-reconfigurable photoresponse, achieving on/off control of spectral response through applied bias. The resonator geometry shows promise for integration at the focal plane array level, even for small pixel sizes.
Article
Chemistry, Multidisciplinary
Erick Arguello Cruz, Pedro Ducos, Zhaoli Gao, Alan T. Charlie Johnson, Dario Niebieskikwiat
Summary: In this study, the effect of ferromagnetic nickel nanoparticles on the magnetotransport properties of chemical-vapor-deposited graphene was characterized. It was found that these nanoparticles greatly suppressed the zero-field peak of resistivity caused by weak localization and enhanced the high-field magnetoresistance. The interaction between the graphene and the nickel nanoparticles was attributed to a local exchange coupling, which did not affect the intrinsic transport parameters of graphene, indicating that the changes in magnetotransport properties were purely magnetic in origin.
Article
Nanoscience & Nanotechnology
Nishal Shah, Vasant Iyer, Zhiping Zhang, Zhaoli Gao, Juhwan Park, Venkata Yelleswarapu, Firooz Aflatouni, A. T. Charlie Johnson, David Issadore
Summary: We developed CMOS-compatible graphene Hall sensors integrated with PDMS microfluidics for magnetic sensing in blood, which can overcome the limitations of traditional technologies in clinical applications, and show high sensitivity and reliability. They can also be integrated with microfluidics and sensing electronics for in-flow detection of magnetic beads.
MICROSYSTEMS & NANOENGINEERING
(2023)
Article
Nanoscience & Nanotechnology
Anis Chiout, Cleophanie Brochard-Richard, Laetitia Marty, Nedjma Bendiab, Meng-Qiang Zhao, A. T. Charlie Johnson, Fabrice Oehler, Abdelkarim Ouerghi, Julien Chaste
Summary: A study has found that the frequency of nanomechanical resonators can be effectively tuned at the nanoscale using a suspended MoS2 membrane heated by the Joule effect, with a significantly larger modulation amplitude compared to other approaches. This research is crucial for fully harnessing the potential of two-dimensional materials.
NPJ 2D MATERIALS AND APPLICATIONS
(2023)
Article
Materials Science, Multidisciplinary
Geoffroy Kremer, Aymen Mahmoudi, Meryem Bouaziz, Cleophanie Brochard-Richard, Lama Khalil, Debora Pierucci, Francois Bertran, Patrick Le Fevre, Mathieu G. Silly, Julien Chaste, Fabrice Oehler, Marco Pala, Federico Bisti, Abdelkarim Ouerghi
Summary: Metal monochalcogenides, such as InTe, exhibit diverse electronic properties based on their chemical composition, layer numbers, and stacking order. This study combined angle-resolved photoemission spectroscopy and density functional theory calculations to reveal the stability and properties of InTe. It was found that InTe has a tetragonal crystal structure, semiconducting behavior, and intrinsic p-type doping. The electronic band structure of InTe was highly anisotropic, with a large effective mass and in-plane anisotropy, making it interesting for electronic and thermoelectric applications.
PHYSICAL REVIEW MATERIALS
(2023)
