Article
Nanoscience & Nanotechnology
Artur P. Herman, Szymon J. Zelewski, Kamil Misztal, Robert Kudrawiec
Summary: In this study, long-lived free charge carriers generated from excitons in MoS2, MoSe2, WS2, and WSe2 crystals were observed using TRMC for the first time. The lifetime of these carriers depends on surface and defect states as well as surface band bending.
Article
Multidisciplinary Sciences
Thomas J. Bullard, Kyle Frische, Charlie Ebbing, Stephen J. Hageman, John Morrison, John Bulmer, Enam A. Chowdhury, Michael L. Dexter, Timothy J. Haugan, Anil K. Patnaik
Summary: We examined the electromagnetic emission from two photo-illuminated linear arrays composed of inductively charged superconducting ring elements. The arrays were illuminated by an ultrafast infrared laser, triggering microwave broadband emission. Increasing the element count and frequency resulted in a narrowing of the forward radiation lobe, demonstrating directed GHz emission. This study suggests the potential for achieving higher frequencies and a larger number of elements, enabling a unique pulsed array emitter concept spanning from microwave to terahertz frequencies.
SCIENTIFIC REPORTS
(2023)
Article
Materials Science, Multidisciplinary
Z. Ruan, Jianchen Lu, Baijin Li, Qizan Chen, Zhenliang Hao, Lei Gao, Jinming Cai
Summary: In this study, a comprehensive investigation of intrinsic defects in single-layer WS2 grown by chemical vapor deposition was conducted. The results provide guidance for future targeted defect engineering and doping of single-layer transition metal dichalcogenides.
MATERIALS TODAY PHYSICS
(2022)
Article
Chemistry, Physical
Chao Hou, Jingwen Deng, Jianxin Guan, Qirong Yang, Zhihao Yu, Yilin Lu, Zihan Xu, Zefan Yao, Junrong Zheng
Summary: The research reveals that laser irradiation can enhance the photoluminescence of monolayer MoS2, with different effects observed under different atmospheres, being more significant in the presence of oxygen. Additionally, physically adsorbed water also plays a role in enhancing the photoluminescence of monolayer MoS2.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2021)
Article
Physics, Applied
Xiaopeng Wang, Gianluca Fabi, Reet Chaudhuri, Austin Hickman, Mohammad Javad Asadi, Kazuki Nomoto, Huili Grace Xing, Debdeep Jena, Marco Farina, James C. M. Hwang
Summary: Using a scanning microwave microscope (SMM), researchers have found that it is possible to characterize subsurface electromagnetic properties of nanoelectronic structures nondestructively. By removing the topography information, the sheet resistance of 2D electron or hole gas buried at the interface of a heterostructure can be extracted from the SMM data. This study is important for improving SMM technology and monitoring local sheet resistance during device manufacturing.
APPLIED PHYSICS LETTERS
(2022)
Article
Chemistry, Multidisciplinary
Michael Hartelt, Pavel N. Terekhin, Tobias Eul, Anna-Katharina Mahro, Benjamin Frisch, Eva Prinz, Baerbel Rethfeld, Benjamin Stadtmueller, Martin Aeschlimann
Summary: This paper discusses the importance of understanding the differences between photon-induced and plasmon-induced hot electrons and proposes a method using a femtosecond pump-probe scheme combined with theoretical analysis to separate the energy and momentum distribution of plasmon-induced hot electrons.
Article
Chemistry, Physical
Shubham Agrawal, Peng Bai
Summary: This study demonstrates a simple and precise method to directly track and analyze in-situ interfaces on mesoscale in practical porous electrodes to obtain true local current density. The results show that the local current density is two orders of magnitude higher than the globally averaged current density. The study sheds light on the long-standing discrepancies in kinetics parameters derived from electroanalytical measurements and first principle predictions.
ADVANCED ENERGY MATERIALS
(2021)
Review
Nanoscience & Nanotechnology
Guillermo D. Brinatti Vazquez, Giulia Lo Gerfo Morganti, Alexander Block, Niek F. van Hulst, Matz Liebel, Klaas-Jan Tielrooij
Summary: This review introduces a technique called spatiotemporal microscopy that enables the study of transport phenomena such as diffusion, convection, and drift with high spatial and high temporal resolution. The technique offers broad applications and can observe movement of different species at nanometer and femtosecond scales.
ADVANCED ELECTRONIC MATERIALS
(2023)
Article
Chemistry, Multidisciplinary
Jian Zhang, Lutao Li, Ming Du, Yan Cui, Yonghua Li, Wei Yan, Huajie Huang, Xing'ao Li, Xinbao Zhu
Summary: Efficient and nonprecious cocatalysts play a crucial role in improving the photocatalytic performance of semiconductors. A novel CoP cocatalyst with single-atom phosphorus vacancies defects (CoP-V-p) is synthesized and coupled with Cd0.5Zn0.5S to build a heterojunction photocatalyst. The nanohybrids show a significantly higher photocatalytic hydrogen production activity compared to the pristine ZCS samples.
Article
Chemistry, Physical
Joao Pereira, Yuniki Mediayati, Tom Sleutels, Francisco Fabregat-Santiago, Annemiek ter Heijne
Summary: This study used EIS and OCT to estimate charge carriers and study mass transfer limitations in intermittently polarized anodic EABfs. The results show that EIS can be used for non-destructive real-time studies of developing EABfs.
JOURNAL OF POWER SOURCES
(2023)
Article
Instruments & Instrumentation
Leonard Weihao Cao, Chen Wu, Rajarshi Bhattacharyya, Ruolun Zhang, Monica T. Allen
Summary: Microwave Impedance Microscopy (MIM) is a near-field imaging technique used for visualizing the conductivity of materials at the nanoscale. It has shown great potential in the study of topological states, correlated electronic states, and quantum materials. We have developed a novel low-temperature MIM integrated into a dilution refrigerator to explore these low-energy phenomena.
REVIEW OF SCIENTIFIC INSTRUMENTS
(2023)
Article
Materials Science, Multidisciplinary
Aswin Asaithambi, Roland Kozubek, Gunther M. Prinz, Francesco Reale, Erik Pollmann, Marcel Ney, Cecilia Mattevi, Marika Schleberger, Axel Lorke
Summary: The study found that irradiating WS2 monolayers with Xe30+ ions can create different defect densities, which exhibit different luminescent properties at various temperatures. Furthermore, using laser excitation and adjusting temperature can also modify the luminescence properties of WS2 monolayers.
PHYSICA STATUS SOLIDI-RAPID RESEARCH LETTERS
(2021)
Article
Chemistry, Multidisciplinary
Artem O. Denisov, Seong W. Oh, Gordian Fuchs, Adam R. Mills, Pengcheng Chen, Christopher R. Anderson, Mark F. Gyure, Arthur W. Barnard, Jason R. Petta
Summary: Researchers have successfully combined the spatial resolution of scanning probe microscopy with the speed of microwave measurements by coupling a metallic tip to a Si/SiGe double quantum dot. They were able to observe excited states with an energy of -65microelectronvolts, consistent with valley splittings in Si/SiGe.
Article
Physics, Applied
Jun-Yi Shan, Adam Pierce, Eric Y. Ma
Summary: Microwave impedance microscopy (MIM) is a promising scanning probe technique that measures the local complex dielectric function. This study presents a systematic analysis of the dependence of MIM signal on various important design parameters, providing guidance for different design goals.
APPLIED PHYSICS LETTERS
(2022)
Article
Physics, Applied
Jun-Yi Shan, Nathaniel Morrison, Eric Y. Ma
Summary: The recently developed technique of transmission-mode microwave impedance microscopy greatly expands the capabilities of standard reflection-mode MIM for studying nanoscale electro-acoustic devices. However, there is a lack of systematic design principles for boosting sensitivity and balancing bandwidth. This study shows that the T-MIM signal is proportional to the reflection-mode voltage enhancement factor of the circuit, as long as the output impedance of the local voltage source is properly treated. The authors demonstrate a realistic path for achieving this proportionality using commercially available superconducting components and critically coupled impedance matching networks.
APPLIED PHYSICS LETTERS
(2023)
Article
Chemistry, Multidisciplinary
Chenhui Zhang, Chen Liu, Junwei Zhang, Youyou Yuan, Yan Wen, Yan Li, Dongxing Zheng, Qiang Zhang, Zhipeng Hou, Gen Yin, Kai Liu, Yong Peng, Xi-Xiang Zhang
Summary: This study reports a layered crystal structure transition metal dichalcogenide, Cr1+xTe2, that hosts room-temperature skyrmions and exhibits large topological Hall effect (THE). By manipulating the intercalation, the Curie temperature and magnetic anisotropy of the material can be controlled. Room-temperature skyrmions are successfully created in Cr1.53Te2, which have a relatively weak perpendicular magnetic anisotropy and induce a sign reversal of THE at low temperatures.
ADVANCED MATERIALS
(2023)
Article
Nanoscience & Nanotechnology
Yue Luo, Nannan Mao, Dapeng Ding, Ming-Hui Chiu, Xiang Ji, Kenji Watanabe, Takashi Taniguchi, Vincent Tung, Hongkun Park, Philip Kim, Jing Kong, William L. Wilson
Summary: In-plane anisotropic exciton-polariton propagation in SnSe allows for nanoscale imaging of in-plane ferroelectric domains. The control and manipulation of exciton-polaritons in two-dimensional quantum materials has the potential for nanoscale control of electromagnetic fields. By studying the propagation dynamics and dispersion of exciton-polaritons in SnSe, a group-IV monochalcogenide semiconductor, it was found that this propagation enables imaging of the in-plane ferroelectric domains. Additionally, electric switching of exciton-polaritons in the ferroelectric domains of this complex van der Waals system was demonstrated, suggesting the potential for reconfigurable polaritonic optical devices.
NATURE NANOTECHNOLOGY
(2023)
Article
Chemistry, Multidisciplinary
Zhipeng Hou, Qingping Wang, Qiang Zhang, Senfu Zhang, Chenhui Zhang, Guofu Zhou, Xingsen Gao, Guoping Zhao, Xixiang Zhang, Wenhong Wang, Junming Liu
Summary: This study experimentally explores the current-driven dynamics of elliptically distorted skyrmions in geometrically confined magnet Fe3Sn2. It is found that the elliptical skyrmions can reversibly split into smaller-sized circular skyrmions at a specific current density with the current injected along their minor axis. The results indicate that the morphology provides a new degree of freedom for manipulating the current-driven dynamics of skyrmions, offering a compelling route for the future development of spintronic devices.
Article
Nanoscience & Nanotechnology
Xin He, Chenhui Zhang, Dongxing Zheng, Peng Li, John Q. Xiao, Xixiang Zhang
Summary: With the recent advancements in two-dimensional ferromagnets, it is now feasible to develop high-quality all-2D spintronic devices. In this study, nonlocal spin valves were successfully fabricated using Fe3GeTe2 as the spin source and detector and multilayer graphene as the spin transport channel. The spin transport signal strongly depended on temperature and vanished below the Curie temperature of the Fe3GeTe2 flakes. Our results suggest potential applications of van der Waals heterostructures in spintronic devices.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Chemistry, Multidisciplinary
Areej Aljarb, Jiacheng Min, Mariam Hakami, Jui-Han Fu, Rehab Albaridy, Yi Wan, Sergei Lopatin, Dimitrios Kaltsas, Dipti Naphade, Emre Yengel, Mohamed Nejib Hedhili, Roaa Sait, Abdul-Hamid Emwas, Arwa Kutbee, Merfat Alsabban, Kuo-Wei Huang, Kaimin Shih, Leonidas Tsetseris, Thomas D. Anthopoulos, Vincent Tung, Lain-Jong Li
Summary: Growing continuous monolayer films of TMDs without disrupting grain boundaries is a challenge. The presence of an interfacial reconstructed (IR) layer within the substrate-epilayer gap affects the orientations of nucleating TMDs domains and materials' properties. These findings have implications for the development of TMD-based electronics and optoelectronics.
Article
Chemistry, Multidisciplinary
Julian Klein, Benjamin Pingault, Matthias Florian, Marie-Christin Heissenbuettel, Alexander Steinhoff, Zhigang Song, Kierstin Torres, Florian Dirnberger, Jonathan B. Curtis, Mads Weile, Aubrey Penn, Thorsten Deilmann, Rami Dana, Rezlind Bushati, Jiamin Quan, Jan Luxa, Zdenek Sofer, Andrea Alu, Vinod M. Menon, Ursula Wurstbauer, Michael Rohlfing, Prineha Narang, Marko Loncar, Frances M. Ross
Summary: In this study, it was found that the magnetic semiconductor CrSBr behaves like a quasi-1D material in a magnetically ordered environment. The strong 1D electronic character of CrSBr originates from the Cr-S chains and the weak interlayer hybridization, leading to anisotropy in effective mass and dielectric screening. Moreover, CrSBr hosts spectrally narrow excitons of high binding energy and oscillator strength due to reduced dimensionality and interlayer coupling. Overall, CrSBr is an experimentally attractive candidate for the study of exotic exciton and 1D-correlated many-body physics.
Article
Chemistry, Multidisciplinary
Aitian Chen, Ren-Ci Peng, Bin Fang, Tiannan Yang, Yan Wen, Dongxing Zheng, Chenhui Zhang, Chen Liu, Zibin Li, Peisen Li, Yan Li, Yonggang Zhao, Ce-Wen Nan, Ziqiang Qiu, Long-Qing Chen, Xi-Xiang Zhang
Summary: This study successfully demonstrates voltage-driven full resistance switching of a magnetic tunnel junction (MTJ) with dipole interaction on a ferroelectric substrate through switchable parallel/antiparallel magnetization alignment. By rotating the magnetic easy axis via strain-mediated magnetoelectric coupling, the parallel magnetizations in the MTJ reorient to the x axis with opposite paths because of dipole interaction, thus resulting in antiparallel alignment. Moreover, this voltage switching of MTJs is nonvolatile and can be well understood via phase field simulations. These results provide an avenue to realize electrical switching of MTJs and are significant for exploring energy-efficient spintronic devices.
ADVANCED FUNCTIONAL MATERIALS
(2023)
Article
Chemistry, Multidisciplinary
Nannan Mao, Yue Luo, Ming-Hui Chiu, Chuqiao Shi, Xiang Ji, Tymofii S. S. Pieshkov, Yuxuan Lin, Hao-Lin Tang, Austin J. J. Akey, Jules A. A. Gardener, Ji-Hoon Park, Vincent C. Tung, Xi Ling, Xiaofeng Qian, William L. L. Wilson, Yimo Han, William A. A. Tisdale, Jing Kong
Summary: Thin ferroelectric material SnSe with nanometer-scale ferroelectric domains exhibiting giant nonlinear optical effect and coherent enhancement of second-harmonic fields was reported. The ferroelectric domains show 90 degrees/270 degrees twin boundaries or 180 degrees domain walls and have parallel and antiparallel stacking of neighboring van der Waals ferroelectric layers. The second-harmonic generation in SnSe was observed to be 100 times more intense than monolayer WS2, demonstrating its potential in on-chip nonlinear optical components and nonvolatile memory devices.
ADVANCED MATERIALS
(2023)
Article
Nanoscience & Nanotechnology
Kwan-Ho Kim, Seyong Oh, Merrilyn Mercy Adzo Fiagbenu, Jeffrey Zheng, Pariasadat Musavigharavi, Pawan Kumar, Nicholas Trainor, Areej Aljarb, Yi Wan, Hyong Min Kim, Keshava Katti, Seunguk Song, Gwangwoo Kim, Zichen Tang, Jui-Han Fu, Mariam Hakami, Vincent Tung, Joan M. M. Redwing, Eric A. A. Stach, Roy H. H. Olsson, Deep Jariwala
Summary: Three-dimensional monolithic integration of memory devices with logic transistors is crucial for enhancing computational power and energy efficiency in big data applications, such as artificial intelligence. However, there is still a need for reliable, compact, fast, energy-efficient, and scalable memory devices. In this study, back-end-of-line-compatible FE-FETs using two-dimensional MoS2 channels and AlScN ferroelectric materials were successfully demonstrated, showing promising performance and stability in memory retention and endurance. This research paves the way for the integration of two-dimensional semiconductor memory with silicon complementary metal-oxide-semiconductor logic in a three-dimensional heterostructure.
NATURE NANOTECHNOLOGY
(2023)
Article
Multidisciplinary Sciences
Xin He, Yinchang Ma, Chenhui Zhang, Aiping Fu, Weijin Hu, Yang Xu, Bin Yu, Kai Liu, Hua Wang, Xixiang Zhang, Fei Xue
Summary: Using protonic gating technology, this study creates a series of metastable ferroelectric phases in layered alpha-In2Se3 transistors and demonstrates their reversible transitions. Protons can be incrementally injected or extracted by varying the gate bias, enabling controllable tuning of the ferroelectric alpha-In2Se3 protonic dynamics and obtaining numerous intermediate phases. The volatile gate tuning of alpha-In2Se3 protonation and the formation of metastable hydrogen-stabilized alpha-In2Se3 phases are unexpectedly discovered. Ultralow gate voltage switching of different phases is achieved, providing a possible avenue for accessing hidden phases in ferroelectric switching.
Article
Engineering, Electrical & Electronic
Alok Ranjan, Sesn J. O'Shea, Andrea Padovani, Tong Su, Paolo La Torraca, Yee Sin Ang, Manveer Singh Munde, Chenhui Zhang, Xixiang Zhang, Michel Bosman, Nagarajan Raghavan, Kin Leong Pey
Summary: We used conduction atomic force microscopy (CAFM) to investigate the soft breakdown of monocrystalline hexagonal boron nitride (h-BN) and analyzed the defect generation and dielectric degradation by charge transport simulations and density functional theory (DFT) calculations. The results showed that defects were gradually generated over time, leading to an increase in current before dielectric breakdown. Different types of defects were observed, with defects formed from adjacent boron and nitrogen monovacancies having the lowest formation energy. The electrical shorting between layers due to the formation of these defects was confirmed by charge transport simulations, while physical removal of h-BN layers during soft breakdown was ruled out.
ACS APPLIED ELECTRONIC MATERIALS
(2023)
Article
Engineering, Electrical & Electronic
Yakun Liu, Guoyi Shi, Dushyant Kumar, Taeheon Kim, Shuyuan Shi, Dongsheng Yang, Jiantian Zhang, Chenhui Zhang, Fei Wang, Shuhan Yang, Yuchen Pu, Peng Yu, Kaiming Cai, Hyunsoo Yang
Summary: In this study, we report the field-free switching of perpendicular magnetic anisotropy ferromagnet cobalt iron boron using out-of-plane spin-polarized current generated by the Weyl semimetal tantalum iridium telluride. Our results suggest that TaIrTe4 is an efficient spin current source for field-free spin-orbit torque applications.
NATURE ELECTRONICS
(2023)
Article
Chemistry, Multidisciplinary
Aitian T. Chen, Hong-Guang Piao, Chenhui Zhang, Xiao-Ping Ma, Hanin Algaidi, Yinchang Ma, Yan Li, Dongxing Zheng, Ziqiang Qiu, Xi-Xiang Zhang
Summary: In spintronics, controlling the orientation of ordered magnetic domains is crucial for various applications. This study shows that by applying electric fields to a ferroelectric substrate, ordered magnetic strip domains in Ni films can be switched between the y- and x-axes, providing an energy-efficient approach for manipulating magnetic domains using electric fields.
MATERIALS HORIZONS
(2023)
Article
Chemistry, Physical
Rohan Paste, Shenghan Li, Jui-Han Fu, Yu-Hsiang Chiang, Arif I. Inamdar, Ming-Hsi Chiang, Vincent Tung, Hong-Cheu Lin, Chih Wei Chu
Summary: Stable lithium-sulfur batteries have the potential to be the next generation of stable energy-storage devices. This study introduces a modified separator (MC separator) with crumpled MoS2 nanosheets, which can adsorb lithium polysulfides and provide additional reaction sites, leading to enhanced specific capacity and cycling stability of the battery.
JOURNAL OF MATERIALS CHEMISTRY A
(2023)
Article
Chemistry, Physical
Ning Li, Chenhui Zhang, Weizheng Liang, Yaohua Jiang, Xi-Xiang Zhang, Yang Mi, Sheng-Nian Luo
Summary: This work investigates the generation mechanism and relaxation dynamics of coherent phonons in Fe1.14Te, the parent compound of chalcogenide superconductors, using femtosecond transient optical spectroscopy. The experimental results show that the phonon frequency decreases with increasing temperature, while the phonon dephasing time is temperature independent. The maximum photosusceptibility of the A(1g) phonons is obtained through the resonance Raman effect.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2023)
