Article
Chemistry, Multidisciplinary
Weifeng Zhang, He Hao, Yangjin Lee, Yan Zhao, Lianming Tong, Kwanpyo Kim, Nan Liu
Summary: This study successfully fabricated multilayer Moire superlattices with only one twisted interface and systematically studied their twist-angle dependent optical properties. The results showed that the twisted multilayers exhibited higher photoluminescence intensity and tunable interlayer coupling, indirect bandgap, and degree of circular polarization.
ADVANCED FUNCTIONAL MATERIALS
(2022)
Article
Chemistry, Multidisciplinary
Kenjiro Hayashi, Masako Kataoka, Hideyuki Jippo, Junichi Yamaguchi, Mari Ohfuchi, Shintaro Sato
Summary: This study investigates the effects of grain boundaries on the sensing properties of polycrystalline layered materials. The results show that while the CVD-grown film has superior electrical properties, the TVS-grown film exhibits higher sensitivity to NO2. Transmission electron microscopy observations reveal the presence of rotationally oriented grains and mirror twin grain boundaries in the TVS-grown film.
Article
Materials Science, Multidisciplinary
Yupeng Xing, Kailiang Zhang, Jinshi Zhao, Zhengchun Yang, Yujie Yuan, Wei Li
Summary: The photovoltaic characteristics of monolayer MoS2/multilayer MoS2 vertical heterojunction ultrathin solar cell were calculated, and the highest efficiency of the cell could reach 16.8% under specific conditions.
Article
Chemistry, Multidisciplinary
Yingjie Chen, Baonan Jia, Guoying Qin, Huiyan Zhao, Lihong Han, Pengfei Lu
Summary: High-performance photocatalysts are crucial for harvesting solar energy and producing pollution-free hydrogen and oxygen through water splitting. In this study, we designed 144 van der Waals (vdW) heterostructures by combining different two-dimensional (2D) group III-V MX (M = Ga, In and X = P, As) monolayers to identify efficient photoelectrochemical materials. Using first-principles calculations, we investigated the stabilities, electronic properties, and optical properties of these heterostructures. GaP/InP in a BB-II stacking configuration was selected as the most promising candidate, with a type-II band alignment and suitable gap value for the catalytic reaction under pH = 0. Additionally, the construction of vdW heterostructure improved light absorption. These findings provide insights into the properties of III-V heterostructures and can guide experimental synthesis for photocatalysis applications.
Article
Chemistry, Analytical
Yousheng Ye, Shasha Li, An Ping, Xinjun Wan, Jianguo Li
Summary: In this study, a highly efficient MoS2 quantum dot ECL sensor was utilized for the detection of melamine residues in milk powder, showing good sensitivity and reliability compared to traditional detection methods.
ANALYTICAL METHODS
(2021)
Article
Engineering, Environmental
Bo Gao, Yiwei Zhao, Xiaoye Du, Dan Li, Shujiang Ding, Yanhuai Li, Chunhui Xiao, Zhongxiao Song
Summary: High 1T phase-ratio MoS2 was synthesized with the assistance of cobalt and nickel through a mild hydrothermal method, showing excellent hydrogen evolution reaction performance. The phase transition was induced by electron injection during cobalt and nickel co-doping, leading to abundant 1T-phase and smaller hydrogen adsorption/desorption energy.
CHEMICAL ENGINEERING JOURNAL
(2021)
Review
Crystallography
Omnia Samy, Shuwen Zeng, Muhammad Danang Birowosuto, Amine El Moutaouakil
Summary: Molybdenum disulfide (MoS2) is a compound with outstanding features and wide applications, playing important roles in electronics and energy, as well as significant effects in detecting diseases like cancer and Alzheimer's.
Article
Nanoscience & Nanotechnology
Minji Chae, Yeongseo Han, Yoon Hee Park, Dahyun Choi, Yoojin Choi, Sooyeon Kim, Inseon Song, Changhyun Ko, Min-Kyu Joo
Summary: Researchers propose a simple yet powerful contact electrode design to enhance the interlayer carrier injection efficiency along the thickness, providing an advanced electronic device platform for high-performing 2D optoelectronic devices.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Chemistry, Physical
Uri R. Gabinet, Changyeon Lee, Na Kyung Kim, Martin Hulman, Sarah M. Thompson, Cherie R. Kagan, Chinedum O. Osuji
Summary: Molybdenum disulfide nanosheets exhibit anisotropic optical and electronic properties, and their orientation can be controlled to uncover and utilize these properties.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2022)
Article
Nanoscience & Nanotechnology
Di Liu, Yixuan Bian, Zhiwei Zhu, Yuanhua Shao, Meixian Li
Summary: The electro-oxidation mechanism of molybdenum disulfide nanomaterials and its application in the construction of ultrasensitive electrochemical sensor for the detection of trace water were investigated.
ACS APPLIED MATERIALS & INTERFACES
(2022)
Article
Materials Science, Multidisciplinary
Grazia Giuseppina Politano, Marco Castriota, Maria Penelope De Santo, Mario Michele Pipita, Giovanni Desiderio, Carlo Vena, Carlo Versace
Summary: Molybdenum disulfide (MoS2) among Transition Metal Dichalcogenides (TMDCs) has sparked interest due to its potential applications, particularly in solution-based applications. However, lack of knowledge about its optical properties has hindered its use. This study investigated the broadband optical properties of MoS2 films deposited by spin-coating on Si/SiO2 substrates using micro-Raman spectroscopy and Variable Angle Spectroscopic Ellipsometry (VASE).
Article
Multidisciplinary Sciences
Zixiao Wang, Ben Niu, Bo Jiang, Hong-Yuan Chen, Hui Wang
Summary: This work demonstrates plasmonic-based phase imaging to visualize the switching and suppression processes of electron-doping and conductivity regime in a monolayer of MoS2. The intermediate states of electrical switching in MoS2 are observed through ultrasensitive phase variation of a single gold nanoparticle. This research has potential applications in novel nanoelectronics and optoelectronics.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2022)
Article
Spectroscopy
Yaping Zhong, Lijuan Guo, Yibiao Zou, Yu Chen, Zhentan Lu, Dong Wang
Summary: We propose a rapid and ratiometric fluorescent detection method for hypochlorite using glutathione functionalized molybdenum disulfide quantum dots (G-MoS2 QDs). The G-MoS2 QDs are obtained through a hydrothermal method with maximum fluorescence intensity at 430 nm under excitation of 360 nm. This detection method takes only 30 s at room temperature and has a limit of detection of 11.5 nM.
SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY
(2023)
Article
Chemistry, Physical
Li Gong, Xiao Mu, Qiang Li, Lei Ma, Yucong Xiong, Rong Li
Summary: An efficient electrocatalyst NC@Mo2C@MoS2-(Ni) was designed for the Hydrogen Evolution Reaction in water electrolysis, showing good catalytic performance in both acidic and basic media. This work not only fabricates a catalyst for hydrogen evolution, but also provides a method to design more efficient functional electrocatalysts.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2021)
Article
Nanoscience & Nanotechnology
Gabriele Pippia, Anastasia Rousaki, Matteo Barbone, Jonas Billet, Rosaria Brescia, Anatolii Polovitsyn, Beatriz Martin-Garcia, Mirko Prato, Francesco De Boni, Marko M. Petric, Amine Ben Mhenni, Isabel Van Driessche, Peter Vandenabeele, Kai Mueller, Iwan Moreels
Summary: Transition-metal dichalcogenide nano-sheets have attracted significant attention in the field of 2D nanomaterials due to their direct semiconductor nature and broken inversion symmetry in odd-layer number. Colloidal synthesis has emerged as a cost-efficient and scalable method, but obtaining monolayers remains challenging.
ACS APPLIED NANO MATERIALS
(2022)
Article
Materials Science, Multidisciplinary
Roman Morgunov, Ekaterina Kunitsyna, Ruslan Allayarov, Oksana Koplak, Stephane Mangin
Summary: The effect of a ferromagnetic magnetoresistive sensor on the magnetic susceptibility of nanoparticles (NPs) deposited on its surface is presented in this study. It is found that the deposition of CoFe2O4 nanoparticles on a CoFeB/Ta/CoFeB platform, consisting of thin ferromagnetic layers, changes the blocking temperature of the NPs. This change in temperature is attributed to the magnetic dipole interaction between the NPs and the platform, which affects the frequency and field dependences of the NPs' blocking temperature. The results obtained demonstrate the importance of considering the backward effect of the sensor for the correct application of magnetoresistive and low-frequency inductive sensors in medicine and biology.
JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS
(2022)
Article
Physics, Applied
Jon Gorchon, Stephane Mangin, Michel Hehn, Gregory Malinowski
Summary: THz emission from magnetic films is an important characterization tool for spintronic properties, but extracting absolute numbers remains extremely challenging due to the complex conversion mechanisms and high sensitivity to changes in optical properties.
APPLIED PHYSICS LETTERS
(2022)
Article
Multidisciplinary Sciences
Quentin Remy, Julius Hohlfeld, Maxime Verges, Yann Le Guen, Jon Gorchon, Gregory Malinowski, Stephane Mangin, Michel Hehn
Summary: Under laser illumination, a ferromagnet can lose its magnetization through ultrafast demagnetization and phase transition. By overcoming the critical slowing down, magnetization can be reversed in a few hundreds of femtoseconds through ultrafast spin cooling and spin heating mechanisms. This has potential applications in ultrafast and energy efficient magnetic memory and storage devices.
NATURE COMMUNICATIONS
(2023)
Article
Physics, Applied
Lingfang Xu, Minghang Song, Wenjun Yi, Hanshuo Fang, Ruilong Wang, Shiheng Liang, Haibo Xiao, Changping Yang
Summary: This paper investigates the effect of electric field amplitude (E-0) and frequency (f) on the dynamic hysteresis in organic ferroelectric copolymer thin films. Three stages of hysteresis area vs field strength are observed. In the first stage, the area (<A>) follows a proportional relationship with E-0, while the distribution of <A> varies with frequency f. In the second stage, the relationship between <A> and E-0(beta) is not applicable, but a relationship of <A> proportional to f(-0.18636) is found. In the third stage, a scaling law is observed with <A> proportional to f(0.08447)E(0)(0.49394) indicating the presence of chiral domains.
JOURNAL OF APPLIED PHYSICS
(2023)
Article
Physics, Applied
M. Bakhmetiev, O. Koplak, J. -L Bello, S. Mangin, R. Morgunov
Summary: In this study, the magnetization reversal in perpendicular GdFeCo/Ir/GdFeCo synthetic ferrimagnets was characterized using AHE measurements. The AHE hysteresis loop, obtained with a perpendicular field, consists of three sub-loops, with two of them being symmetrically biased with respect to the third one. The magnetic field switching for two of the transitions was found to be dependent on the magnetic history, and exposure to an in-plane field led to a reduction of the out-of-plane switching fields in the sub-loops. The unusual dynamics of double domain walls result in unexpected phenomena affecting electrical processes in bilayer structures.
JOURNAL OF APPLIED PHYSICS
(2023)
Article
Chemistry, Physical
Junta Igarashi, Wei Zhang, Quentin Remy, Eva Diaz, Jun-Xiao Lin, Julius Hohlfeld, Michel Hehn, Stephane Mangin, Jon Gorchon, Gregory Malinowski
Summary: The authors demonstrate ultrafast magnetization reversal induced by light in rare-earth-free spin valves of [Pt/Co]/Cu/[Co/Pt] within a picosecond. The discovery of spin-transfer torque (STT) allowed the control of magnetization direction in nanoseconds using electrical current. Ultrashort optical pulses have been used to manipulate the magnetization of ferrimagnets in picoseconds by driving the system out of equilibrium. In this study, the authors show ultrafast magnetization reversal induced by light in commonly used [Pt/Co]/Cu/[Co/Pt] spin valves for STT switching, bridging concepts from spintronics and ultrafast magnetism.
Article
Physics, Multidisciplinary
Cesar Gonzalez-Ruano, Diego Caso, Jabir Ali Ouassou, Coriolan Tiusan, Yuan Lu, Jacob Linder, Farkhad G. Aliev
Summary: Superconductor-ferromagnet tunnel junctions have been used to engineer ultrasensitive terahertz radiation detectors by exploiting their giant thermoelectric effects. In this study, we experimentally observe complete magnetic control over the thermoelectric effects in a superconducting spin valve, including a dependence on the magnetism of the spin valve. The application of high in-plane magnetic fields leads to a double sign inversion of the thermoelectric effect, which remains large even at fields twice the superconducting critical field.
PHYSICAL REVIEW LETTERS
(2023)
Editorial Material
Physics, Applied
Tobias Kampfrath, Andrei Kirilyuk, Stephane Mangin, Sangeeta Sharma, Martin Weinelt
Summary: Spintronics aims to extend electronic functionalities by utilizing the spin of electrons as information carrier, and its speed needs to be pushed to femtosecond time scales and terahertz frequencies to be competitive and compatible with other information carriers. Ultrafast and terahertz spintronics utilize optical and electromagnetic pulses to induce spin torque and transport, and provide new insights and applications for spintronics. This Special Topic Collection aims to present the newest developments and future trends in the field of ultrafast and terahertz spintronics.
APPLIED PHYSICS LETTERS
(2023)
Article
Physics, Applied
Julian Hintermayr, Pingzhi Li, Roy Rosenkamp, Youri L. W. van Hees, Junta Igarashi, Stephane Mangin, Reinoud Lavrijsen, Gregory Malinowski, Bert Koopmans
Summary: In this study, we investigate single-shot all-optical switching (AOS) in Tb/Co/Gd/Co/Tb multilayers to establish AOS in synthetic ferrimagnets with high magnetic anisotropy. By varying the thicknesses of Tb, we find that the threshold fluence for switching is largely independent of the Tb content, indicating the dominant role of Co and Gd interactions. Furthermore, using time-resolved MOKE, we determine that the magnetization crosses zero within the first ps after laser excitation.
APPLIED PHYSICS LETTERS
(2023)
Article
Physics, Applied
P. Vallobra, Y. Xu, H. Wang, G. Malinowski, M. Hehn, J. -c. Rojas-Sanchez, S. Mangin
Summary: Recent research has shown that optical control of the exchange bias field in IrMn/[Co/Pt]N heterostructures can create specific nucleation areas and determine the preferential direction of domain wall propagation. Using different features of a femtosecond laser, robust patterns of various shapes and magnetic properties can be designed for observing domain wall propagation, providing an alternative to existing time-consuming patterning methods.
APPLIED PHYSICS LETTERS
(2023)
Article
Physics, Applied
Danny Petty Gweha Nyoma, Maxime Verges, Michel Hehn, Daniel Lacour, Julius Hohlfeld, Sebastiaan van Dijken, Gregory Malinowski, Stephane Mangin, Francois Montaigne
Summary: We demonstrate the single pulse toggle switching of magnetization in GdFeCo disks with perpendicular to film plane anisotropy using 35 fs linearly polarized laser pulses. Two different magnetic states can be observed depending on the laser fluence: deterministic switching or randomly oriented disks. We observe a non-monotonic behavior of fluence thresholds with disk diameter and discuss the different evolution of the thresholds for both phenomenon.
APPLIED PHYSICS LETTERS
(2023)
Article
Physics, Applied
Lingfang Xu, Wenjun Yi, Shiheng Liang, Haibo Xiao, Ruilong Wang, Changping Yang
Summary: The domain reversal dynamics of pristine and 10 wt.% BiFeO3 nanoparticle-embedded P(VDF-TrFE) flexible ferroelectric membranes were investigated. Scaling relations were determined, providing significant insights for copolymer mechanisms and the design of flexible electric devices.
JOURNAL OF APPLIED PHYSICS
(2023)
Article
Physics, Condensed Matter
Chuangwen Wu, Xiangqing Zhou, Guang Zeng, Chen Sun, Peizhi Li, Jiaxu Li, Shiwei Chen, Guang Yang, Shiheng Liang
Summary: This study investigates a T-type field-free spin-orbit torque device with an in-plane magnetic layer coupled to a perpendicular magnetic layer via a non-magnetic spacer. The device utilizes a Co/Ta/CoTb structure and demonstrates deterministic current-induced magnetization switching and asymmetric domain wall motion. The functionality of multistate synaptic plasticity is also demonstrated, making it suitable for spintronic memory and neuromorphic computing applications.
JOURNAL OF PHYSICS-CONDENSED MATTER
(2023)
Article
Chemistry, Physical
Oleg Kurnosikov, Muriel Sicot, Emilie Gaudry, Danielle Pierre, Yuan Lu, Stephane Mangin
Summary: A non-destructive method for visualizing and characterizing buried nano-structures under a metal surface using scanning tunnelling microscopy/spectroscopy (STM/STS) has been developed. The method utilizes quantum well (QW) states to single out and access the nano-objects buried under the metal surface. The burial depth of the nano-objects can be determined by analyzing the oscillatory behavior of electron density at the sample surface, while the spatial distribution of electron density provides additional information about their size and shape.
NANOSCALE HORIZONS
(2023)
Article
Engineering, Electrical & Electronic
Tianyi Ma, Yu Zhu, Pambiang Abel Dainone, Tongxin Chen, Xavier Devaux, Caihua Wan, Sylvie Migot, Gwladys Lengaigne, Michel Vergnat, Yu Yan, Xiufeng Han, Yuan Lu
Summary: This study demonstrates a large sign reversal of tunneling magnetoresistance (TMR) in a Fe/MgAlOx/Fe4N magnetic tunnel junction (MTJ) controlled by the bias voltage. The sign reversal effect is doubled compared to Fe/MgO/Fe4N MTJs, thanks to the better lattice mismatch and less N diffusion. First-principles calculations reveal that the change of TMR sign originates from different symmetry-dependent tunneling channels between Fe and Fe4N electrodes under opposite bias voltages.
ACS APPLIED ELECTRONIC MATERIALS
(2023)