Article
Chemistry, Physical
Willem O. Tromp, Tjerk Benschop, Jian-Feng Ge, Irene Battisti, Koen M. Bastiaans, Damianos Chatzopoulos, Amber H. M. Vervloet, Steef Smit, Erik van Heumen, Mark S. Golden, Yinkai Huang, Takeshi Kondo, Tsunehiro Takeuchi, Yi Yin, Jennifer E. Hoffman, Miguel Antonio Sulangi, Jan Zaanen, Milan P. Allan
Summary: Superconductivity in high-doped cuprate superconductors is found to be qualitatively different from conventional mean-field theory, as the superfluid density vanishes when the transition temperature goes to zero, which contradicts expectations from Bardeen-Cooper-Schrieffer theory. Scanning tunnelling spectroscopy measurements reveal the emergence of nanoscale superconducting puddles in a metallic matrix, driven by gap filling instead of gap closing, indicating that the breakdown of superconductivity is not caused by diminishing pairing interaction.
Article
Multidisciplinary Sciences
Haoxin Zhou, Tian Xie, Takashi Taniguchi, Kenji Watanabe, Andrea F. Young
Summary: This text introduces a study on achieving superconductivity in structurally simple graphene materials. The research found two distinct superconducting regions in structurally metastable crystalline rhombohedral trilayer graphene, providing a model system to test competing theoretical models of superconductivity.
Article
Nanoscience & Nanotechnology
Wanqing Chen, Meysam Sharifzadeh Mirshekarloo, Sally El Meragawi, Geosmin Turpin, Rowan Pilkington, Anastasios Polyzos, Mainak Majumder
Summary: This study reports a photochemical technique for the synthesis of holey graphene oxide and its application in nanofiltration membranes. The membranes made from h-GO nanosheets with 60 nm pores exhibited a significant increase in water permeance and selectivity, attributed to the presence of nanopores and a smaller interlayer distance between h-GO sheets. The method was successfully transitioned to a flow-based synthesis approach, enabling high production rates and automated manufacturing.
ACS APPLIED NANO MATERIALS
(2022)
Article
Chemistry, Physical
Fengchun Jia, Xiao Xiao, Ardo Nashalian, Sophin Shen, Liu Yang, Zhenyang Han, Huaijiao Qu, Tianmei Wang, Zhi Ye, Zhijun Zhu, Linjun Huang, Yanxin Wang, Jianguo Tang, Jun Chen
Summary: This paper summarizes the separation mechanism and preparation methods of graphene oxide (GO) membranes, reviews the structural regulation of GO, and provides an overview of the potential development prospects and challenges of GO membranes.
Article
Chemistry, Multidisciplinary
Xingxing Wei, Taro Matsuyama, Hajime Sato, Dexiu Yan, Pui Man Chan, Kazunori Miyamoto, Masanobu Uchiyama, Yudai Matsuda
Summary: This study identified the biosynthetic gene cluster of Setosusin in the fungus Aspergillus duricaulis and elucidated its biosynthetic pathway through enzyme reconstitution experiments. The crucial role of the cytochrome P450 enzyme SetF in spirofuranone synthesis was revealed, showing its involvement in epoxidation and structural rearrangement processes. Mutagenesis experiments identified Lys303 as a potential catalytic residue important for spirofuranone synthesis.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2021)
Article
Materials Science, Multidisciplinary
Lars Klemeyer, Hun Park, Jiaxing Huang
Summary: The thermal reduction process of graphene oxide (GO) solids varies depending on their geometry, affecting the properties and stability of the resulting graphene materials. The study enriches the understanding of GO materials and provides insights for tuning the thermal reduction process to achieve high-performance engineering graphene materials.
ACS MATERIALS LETTERS
(2021)
Article
Polymer Science
Yankun Chen, Biao Wang
Summary: The thermal degradation behavior of polypropylene (PP) with 20 wt.% diatomite (DM) was investigated using TG-FTIR and GC-MS techniques. The addition of DM lowered the initial decomposition temperature of PP and resulted in the formation of more olefin degradation products. The catalytic effects of DM on the degradation of PP and the changes in PP chain scission pathways were observed.
Review
Construction & Building Technology
Tianxiang Huang, Zengqing Sun
Summary: Geopolymer is an alternative to Portland cement for civil infrastructures, with enhanced mechanical and electrical behaviors achieved by incorporating graphene. The synthesized graphene-geopolymer composites possess functionalities for future infrastructures, but current investigations are still in the laboratory level, facing challenges for further research.
CONSTRUCTION AND BUILDING MATERIALS
(2021)
Article
Chemistry, Multidisciplinary
Ling Xie, Wenhai Xiao, Xiaoyan Shi, Junzhi Hong, Junjie Cai, Kaili Zhang, Lianyi Shao, Zhipeng Sun
Summary: A microwave-assisted hydrothermal approach is used to synthesize VO2 center dot 0.26H(2)O nanobelts@reduced graphene oxide (VO2 center dot 0.26H(2)O@rGO), which shows promise as a cathode material for ZIBs. The VO2 center dot 0.26H(2)O@rGO has a large specific surface area and low charge transfer resistance, leading to improved electrochemical properties. The performance is also attributed to its large lattice spacing, high capacitive Zn2+ storage behavior, fast Zn2+ transfer rate, and stable structure.
CHEMICAL COMMUNICATIONS
(2022)
Article
Engineering, Environmental
Xiangzhe Jiang, Wei Wang, Gang Yu, Shubo Deng
Summary: In this study, the contribution of nanobubbles for PFAS adsorption on pristine and functionalized graphene was investigated using density functional theory and molecular dynamics simulations. It was found that nanobubbles played a significant role in the adsorption mechanisms of PFAS on different graphene surfaces, with a greater impact on long-chain PFAS.
ENVIRONMENTAL SCIENCE & TECHNOLOGY
(2021)
Review
Environmental Sciences
Yasser Vasseghian, Elena-Niculina Dragoi, Fares Almomani, Van Thuan Le
Summary: This review analyzes the use of graphene as an absorbent and catalyst for the degradation of MNZ, investigating the parameters affecting adsorption and photocatalytic degradation while summarizing the basic mechanisms occurring in these processes.
Article
Chemistry, Physical
Divij Ramesh Nalge, Tarak Karmakar, Saswata Bhattacharya, Krishna Bharadwaj Balasubramanian
Summary: Nanopores in graphene monolayers have great potential for molecular separation applications like desalination and carbon capture. First-principles calculations are used to identify a suitable thermodynamic window for growing graphene monolayers with controlled pore size distribution in a chemical vapor deposition system. The resulting graphene monolayers can achieve controllable pore density through annealing, enabling effective desalination of seawater.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2023)
Review
Chemistry, Multidisciplinary
Luis Sousa Lobo, Sonia A. C. Carabineiro
Summary: Carbon formation on steel has become an active research area with important applications using carbon nanotubes or graphene structures. Understanding different reaction mechanisms can simplify complex growth behavior and potentially reduce the time needed for production and property optimization.
Review
Polymer Science
Sara Maira M. Hizam, Adel Mohammed Al-Dhahebi, Mohamed Shuaib Mohamed Saheed
Summary: This review summarizes the recent progress of graphene-based polymeric nanocomposites for ammonia detection, including discussions on gas sensor designs, the pros and cons of graphene to enhance sensor performance, fabrication techniques, detection mechanisms, and future opportunities and challenges.
Article
Chemistry, Physical
Fanfan Chen, Nagendra Athreya, Chunxiao Zhao, Mingye Xiong, Haojing Tan, Jean-Pierre Leburton, Jiandong Feng
Summary: Gating in ion transport plays a crucial role in vital living-substancetransmission processes. However, the understanding of subcontinuum ion transport in subnanometer nanopores is still limited. In this study, we report the ion density-dependent dynamic conductance switching process in biomimetic graphene nanopores and explain the phenomenon by a reversible ion absorption mechanism.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2022)
Review
Chemistry, Multidisciplinary
Iolanda Di Bernardo, Jack Hellerstedt, Chang Liu, Golrokh Akhgar, Weikang Wu, Shengyuan A. Yang, Dimitrie Culcer, Sung-Kwan Mo, Shaffique Adam, Mark T. Edmonds, Michael S. Fuhrer
Summary: Trisodium bismuthide (Na3Bi) is the first experimentally verified topological Dirac semimetal, showcasing unique physical properties and potential for topological electronic devices. Significant progress has been made in synthesizing large-area thin films via molecular beam epitaxy and studying transport phenomena and topological phase transitions in different doping regimes for Na3Bi.
ADVANCED MATERIALS
(2021)
Article
Chemistry, Multidisciplinary
Hae Yeon Lee, Mohammed M. Al Ezzi, Nimisha Raghuvanshi, Jing Yang Chung, Kenji Watanabe, Takashi Taniguchi, Slaven Garaj, Shaffique Adam, Silvija Gradecak
Summary: The optical properties of stacked hexagonal boron nitride films can be continuously tuned by their relative twist angles, leading to the formation of a moire superlattice and a new moire ' sub-band gap with decreasing magnitude as the twist angle changes. This results in tunable luminescence wavelength and intensity increase of over 40 times, demonstrating the potential for dominating optical properties in hBN films for various technological applications.
Article
Physics, Multidisciplinary
Shuigang Xu, Mohammed M. Al Ezzi, Nilanthy Balakrishnan, Aitor Garcia-Ruiz, Bonnie Tsim, Ciaran Mullan, Julien Barrier, Na Xin, Benjamin A. Piot, Takashi Taniguchi, Kenji Watanabe, Alexandra Carvalho, Artem Mishchenko, A. K. Geim, Vladimir I. Fal'ko, Shaffique Adam, Antonio Helio Castro Neto, Kostya S. Novoselov, Yanmeng Shi
Summary: The study of electronic transport properties of twisted monolayer-bilayer graphene reveals highly tunable van Hove singularities that can cause strong correlation effects under optimum conditions by changing the twist angle or applying an electric field. This demonstrates the potential for correlated insulating states in a structure of monolayer and bilayer graphene with a small twist between them.
Article
Computer Science, Hardware & Architecture
Advait Madhavan, Matthew W. Daniels, Mark D. Stiles
Summary: The research proposes to associate race logic with tropical algebra to build temporal circuits systematically, guiding the design of temporally coded tropical circuits. This allows for the expression of high-level timing-based algorithms and systematic exploration of race logic-based temporal architectures by leveraging temporal memory. A state machine operating purely on time-coded wavefronts is designed using analog memristor-based temporal memories for the implementation of a version of Dijkstra's algorithm, demonstrating the potential of temporal computing for significant energy and throughput advantages.
ACM JOURNAL ON EMERGING TECHNOLOGIES IN COMPUTING SYSTEMS
(2021)
Article
Physics, Multidisciplinary
Aydin Cem Keser, Daisy Q. Wang, Oleh Klochan, Derek Y. H. Ho, Olga A. Tkachenko, Vitaly A. Tkachenko, Dimitrie Culcer, Shaffique Adam, Ian Farrer, David A. Ritchie, Oleg P. Sushkov, Alexander R. Hamilton
Summary: Fluid dynamics plays a crucial role in electron transport in solids, transforming electron motion from independent particles to a viscous electron fluid. By modifying device geometry and eliminating unknown parameters, the true intrinsic hydrodynamic properties of the electron system can be revealed.
Article
Multidisciplinary Sciences
Girish Sharma, Indra Yudhistira, Nilotpal Chakraborty, Derek Y. H. Ho, M. M. Al Ezzi, Michael S. Fuhrer, Giovanni Vignale, Shaffique Adam
Summary: The theory of phonon-dominated transport in twisted bilayer graphene explains experimental observations and contrasts with the Planckian dissipation mechanism, shedding light on the mechanisms responsible for the strongly correlated insulating and superconducting phases. Accurate treatment of electron-phonon scattering beyond the usual methods provides insights and concrete predictions for ongoing experiments.
NATURE COMMUNICATIONS
(2021)
Article
Physics, Applied
Jonathan M. Goodwill, Nitin Prasad, Brian D. Hoskins, Matthew W. Daniels, Advait Madhavan, Lei Wan, Tiffany S. Santos, Michael Tran, Jordan A. Katine, Patrick M. Braganca, Mark D. Stiles, Jabez J. McClelland
Summary: The increasing scale of neural networks and their expanding applications have led to a demand for more energy-efficient and memory-efficient artificial intelligence-specific hardware. To address the main issue of the von Neumann bottleneck, in-memory and near-memory architectures, as well as algorithmic methods, can be utilized. The low-power and binary operation of magnetic tunnel junctions (MTJs) have been leveraged for neural network hardware inference, showing the potential for efficient performance even with device imperfections.
PHYSICAL REVIEW APPLIED
(2022)
Article
Nanoscience & Nanotechnology
Axel Hoffmann, Shriram Ramanathan, Julie Grollier, Andrew D. Kent, Marcelo J. Rozenberg, Ivan K. Schuller, Oleg G. Shpyrko, Robert C. Dynes, Yeshaiahu Fainman, Alex Frano, Eric E. Fullerton, Giulia Galli, Vitaliy Lomakin, Shyue Ping Ong, Amanda K. Petford-Long, Jonathan A. Schuller, Mark D. Stiles, Yayoi Takamura, Yimei Zhu
Summary: Neuromorphic computing approaches are becoming increasingly important for efficiently processing large amounts of data. Quantum materials offer unique attributes that can enable new energy-efficient device concepts at the hardware level. This Perspective discusses select examples of these approaches and provides an outlook on the current opportunities and challenges for assembling quantum-material-based devices into larger complex network systems.
Article
Physics, Applied
Jonathan Gibbons, Takaaki Dohi, Vivek P. Amin, Fei Xue, Haowen Ren, Jun -Wen Xu, Hanu Arava, Soho Shim, Hilal Saglam, Yuzi Liu, John E. Pearson, Nadya Mason, Amanda K. Petford-Long, Paul M. Haney, Mark D. Stiles, Eric E. Fullerton, Andrew D. Kent, Shunsuke Fukami, Axel Hoffmann
Summary: Spin torque is a promising tool for driving magnetization dynamics for computing technologies. However, crystal symmetry limits the geometry of spin torques for most conventional spin source materials. Magnetic ordering reduces material symmetry and allows for the production of exotic torques, with antiferromagnets being particularly robust against external fields.
PHYSICAL REVIEW APPLIED
(2022)
Article
Materials Science, Multidisciplinary
Patrick Quarterman, Yabin Fan, Zhijie Chen, Christopher J. Jensen, Rajesh V. Chopdekar, Dustin A. Gilbert, Megan E. Holtz, Mark D. Stiles, Julie A. Borchers, Kai Liu, Luqiao Liu, Alexander J. Grutter
Summary: Using depth- and element-resolved characterization, this study investigates the antiferromagnetic coupling in Y3Fe5O12/permalloy and Y3Fe5O12/Co thin-film heterostructures. The results reveal that the choice of ferromagnet, seed layer, and substrate influences the sample structure and magnetic properties, leading to notable changes in interface coupling sign, magnetic reversal mechanisms, magnetic depth profiles, and domain structure.
PHYSICAL REVIEW MATERIALS
(2022)
Article
Computer Science, Hardware & Architecture
Siyuan Huang, Brian D. Hoskins, Matthew W. Daniels, Mark D. Stiles, Gina C. Adam
Summary: The movement of large quantities of data during deep neural network training poses challenges for machine learning. Strategies such as functional memories based on flash, resistive switches, and magnetic tunnel junctions can store ultra-large models. However, new approaches are needed to minimize hardware overhead, especially for gradient information that cannot be efficiently stored in these memories.
ACM JOURNAL ON EMERGING TECHNOLOGIES IN COMPUTING SYSTEMS
(2023)
Article
Engineering, Electrical & Electronic
Prashansa Mukim, Pragya R. Shrestha, Advait Madhavan, Nitin Prasad, Jason Campbell, Forrest D. Brewer, Mark D. Stiles, Jabez J. McClelland
Summary: Allan deviation is a useful tool for characterizing the time-dependent noise in oscillators and determining its source characteristics. In this study, measurements on a 130 nm, 7-stage ring oscillator revealed that the Allan deviation exhibited expected behavior from 300 K to 150 K but unexpectedly increased from 150 K to 11 K. Further analysis showed that the measured Allan deviation at low temperatures could be well explained by a few random telegraph noise (RTN) sources, which play a significant role in low-frequency noise at lower temperatures.
IEEE ELECTRON DEVICE LETTERS
(2023)
Article
Materials Science, Multidisciplinary
Fei Xue, Mark D. Stiles, Paul M. Haney
Summary: This paper investigates the mechanism of controlling magnetism through spin-orbit torque in ferromagnets, focusing on the two-dimensional monolayer ferromagnet Fe3GeTe2. The study finds that higher order terms play an important role in the magnetic dynamics in this material, enabling magnetic field-free electrical switching.
Article
Engineering, Electrical & Electronic
Nitin Prasad, Prashansa Mukim, Advait Madhavan, Mark D. Stiles
Summary: Simulations of complex-valued Hopfield networks based on spin-torque oscillators can recover phase-encoded images. Tunable delay elements implemented by phase shifting the oscillatory output of the oscillators provide complex weights in a set of memristor-augmented inverters. Pseudo-inverse training is used for storing multiple images, and the energy required for image recovery depends on the desired error level. The simulations show the network performs well when the resonant frequency of the oscillators can be finely tuned and have a small fractional spread, depending on the strength of feedback.
NEUROMORPHIC COMPUTING AND ENGINEERING
(2022)
Article
Materials Science, Multidisciplinary
Danijela Markovic, Matthew W. Daniels, Pankaj Sethi, Andrew D. Kent, Mark D. Stiles, Julie Grollier
Summary: Analytically showing that easy-plane spin Hall nano-oscillators excited by a spin current polarized perpendicularly to the easy plane have phase dynamics similar to Josephson junctions, suitable for neuromorphic computing. Utilizing a specific nanoconstriction geometry, the easy-plane spiking dynamics are maintained in an experimentally feasible architecture. Two elementary neural network blocks essential for neuromorphic computing are simulated, demonstrating the summing and injection of output spikes energies and the multiplication of outputs by synaptic weights.
