Article
Chemistry, Multidisciplinary
Vaishnavi Kateel, Viola Krizakova, Siddharth Rao, Kaiming Cai, Mohit Gupta, Maxwel Gama Monteiro, Farrukh Yasin, Bart Soree, Johan De Boeck, Sebastien Couet, Pietro Gambardella, Gouri Sankar Kar, Kevin Garello
Summary: Current-induced spin-orbit torques (SOTs) are used to manipulate the magnetic state of magnetic tunnel junctions (MTJs) for various applications. However, the need for an external magnetic field limits its practical implementation. In this study, a field-free switching solution is proposed by shaping the SOT channel to create a bend in the SOT current, enabling deterministic switching. Experimental results demonstrate the feasibility of this approach in nanosecond time scales.
Article
Multidisciplinary Sciences
Fehmi Sami Yasin, Jan Masell, Kosuke Karube, Daisuke Shindo, Yasujiro Taguchi, Yoshinori Tokura, Xiuzhen Yu
Summary: Recent studies have demonstrated the control of magnetic skyrmions and antiskyrmions through thermal current, leading to the transformation between different magnetic states and the switching of helical states. This discovery has significant implications for spintronics research and development.
NATURE COMMUNICATIONS
(2023)
Article
Chemistry, Physical
Nicolas Tancogne-Dejean, Florian G. Eich, Angel Rubio
Summary: In this work, the authors used first-principles simulations to study high-harmonic generation in the topological Diract semimetal Na3Bi and analyzed the effect of spin-orbit coupling on the harmonic response. They found that spin-orbit coupling affects the excitation of carriers, modifies the electron velocity in each spin channel, and changes the timing of emitted harmonics. Furthermore, they discovered that spin-orbit coupling directly couples the charge current to the spin currents, suggesting potential applications in high-harmonic spectroscopy of spin currents in solids.
NPJ COMPUTATIONAL MATERIALS
(2022)
Article
Materials Science, Multidisciplinary
Piyush Agarwal, Yingshu Yang, Rohit Medwal, Hironori Asada, Yasuhiro Fukuma, Marco Battiato, Ranjan Singh
Summary: Femtosecond laser-induced photoexcitation of ferromagnet/heavy metal heterostructures can emit broadband terahertz frequencies. The phenomenon is mainly attributed to the direct photoexcitation of the ferromagnet layer, but it is also influenced by a secondary excitation caused by hot electrons from the heavy metal layer.
ADVANCED OPTICAL MATERIALS
(2023)
Article
Materials Science, Multidisciplinary
Andrei Azovtsev, Andrei Nikitchenko, Nikolay A. Pertsev
Summary: The study presents a theoretically efficient spin injector design with reduced energy losses by exciting magnetic dynamics with elastic waves generated in a ferromagnetic-semiconductor heterostructure using a piezoelectric transducer. Micromagnetoelastic simulations demonstrate the successful injection of spin waves into semiconductor material via acoustic waves, resulting in steady-state magnetization precession at the interface. The simulation data further shows significant spin current pumped into GaAs and high spin accumulation at the semiconductor, indicating promising prospects for acoustically driven spin pumping in spintronic devices.
PHYSICAL REVIEW MATERIALS
(2021)
Article
Materials Science, Multidisciplinary
Nilay Maji, J. Panda, A. Santosh Kumar, T. K. Nath
Summary: In this study, efficient electrical spin injection and detection from NFO into p-Si via MgO tunnel barrier was achieved and proved to be promising. The use of oxide magnetic materials in spin injection and detection for room temperature spin-based electronic devices has been demonstrated.
APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING
(2021)
Article
Multidisciplinary Sciences
Peng Tseng, Jyun-Wei Chen, Wen-Jeng Hsueh
Summary: A topological insulators thin-film spin valve with the use of segment gate-controlled potential shows a huge magnetoresistance value higher than 1000% at room temperature, providing high potential for spintronic applications. The results reveal a significant resistance difference between parallel and antiparallel configurations, with the MR effect strongly influenced by factors such as thin-film thickness, gate potential, gate size, and distribution. This research not only enhances the performance of spin-valves at room temperature, but also expands the applications of magnetic memories and spintronic devices.
SCIENTIFIC REPORTS
(2021)
Article
Physics, Applied
Ronghuan Xie, Shun Wang, Li Cai, Xiaotian Cui, Senmiao Liu, Qiang Cao, Changwen Zhang, Qikun Huang, Shishen Yan
Summary: Bulk spin-orbit torque (SOT) driven memristive switching is achieved in perpendicularly magnetized CoPt alloy films by breaking the inversion symmetry using a composition gradient. Analog-like magnetization switching with multiple intermediate states can be obtained by applying current pulses with different amplitudes or repetition number. The programmable magnetization manipulation and controllable switching probability dependent on pulse frequency or repetition number emulate the weight update of synapses and the integrate-and-fire function of neurons, making it a promising candidate for SOT-based neuromorphic hardware.
APPLIED PHYSICS LETTERS
(2022)
Article
Materials Science, Multidisciplinary
Nilay Maji, Subhasis Shit, T. K. Nath
Summary: This article optimized the fabrication of a Ni0.65Zn0.35Fe2O4/MgO/p-Si heterostructure device using the PLD technique and experimentally investigated its structural, electrical, and magnetic features in the temperature range of 100-300 K. The results showed that the heterojunction exhibited positive junction magnetoresistance behavior under the application of an external magnetic field.
FRONTIERS IN MATERIALS
(2021)
Article
Chemistry, Multidisciplinary
Zilu Wang, Pingzhi Li, Mouad Fattouhi, Yuxuan Yao, Youri L. W. Van Hees, Casper F. Schippers, Xueying Zhang, Reinoud Lavrijsen, Felipe Garcia-Sanchez, Eduardo Martinez, Albert Fert, Weisheng Zhao, Bert Koopmans
Summary: Field-free spin-orbit torque (SOT) switching of perpendicular synthetic antiferromagnets (p-SAFs) is achieved through the introduction of an interlayer with Dzyaloshinskii-Moriya interactions (DMIs). The existence of the DMI interlayer is experimentally confirmed, and deterministic field-free switching is demonstrated. The proposed strategy is compatible with magnetic tunnel junction device structure and provides a method for high-performance SOT devices based on p-SAFs.
CELL REPORTS PHYSICAL SCIENCE
(2023)
Article
Nanoscience & Nanotechnology
Jiahao Han, Luqiao Liu
Summary: This paper summarizes the methods for calibrating the charge-spin conversion efficiency in topological insulators and highlights their superiority as spin-orbit torque generators. Additionally, it reviews the results of magnetic switching under reduced current density in topological insulator/ferromagnet heterostructures.
Article
Engineering, Electrical & Electronic
Venkatesh Vadde, Bhaskaran Muralidharan, Abhishek Sharma
Summary: We propose a magnetic tunnel junction (MTJ) device driven by the spin Hall effect (SHE) that can continuously change its resistance when injected with orthogonal spin currents. We develop a hybrid device-circuit simulation platform to design a network that can perform multiple functionalities of a convolutional neural network (CNN). At the atomistic level, we use the Keldysh non-equilibrium Green's function (NEGF) technique coupled with Landau-Lifshitz-Gilbert-Slonczewski (LLGS) equations and the HSPICE circuit simulator. The designed network demonstrates the simultaneous functionality of rectified linear units (ReLU) and max-pooling, with a nontrivial power-error trade-off and energy-efficient design based on unstable free ferromagnets (FMs) with reliable outputs.
IEEE TRANSACTIONS ON ELECTRON DEVICES
(2023)
Article
Physics, Applied
D. J. P. de Sousa, P. M. Haney, J. P. Wang, Tony Low
Summary: The lack of certain crystalline symmetries in nonmagnetic materials with strong spin-orbit coupling allows for unconventional spin Hall responses, which can be used to excite magnetization dynamics in ferromagnetic materials. In this study, we investigate the interplay between conventional and unconventional spin-orbit torques on the magnetization dynamics of a perpendicular ferromagnet and identify different dynamical regimes. Our findings challenge common beliefs about the role of spin Hall angles in magnetization switching and provide insights into maximizing switching efficiency.
PHYSICAL REVIEW APPLIED
(2022)
Review
Chemistry, Multidisciplinary
Tianhan Liu, Paul S. Weiss
Summary: This Perspective discusses the inconsistent definitions, calculations, and analysis methods of spin polarization in chirality-induced spin selectivity (CISS). It proposes a practical and meaningful figure of merit through quantitative analysis of magnetoresistance in CISS transport studies.
Article
Chemistry, Physical
Mara Strungaru, Mathias Augustin, Elton J. G. Santos
Summary: Research has found that ultrafast laser pulses can manipulate the magnetic properties of recently discovered 2D vdW materials and induce the formation and control of nontrivial topological spin textures.
NPJ COMPUTATIONAL MATERIALS
(2022)
Article
Engineering, Electrical & Electronic
Ahmed Kamal Reza, Mohammad Khaled Hassan, Kaushik Roy
IEEE TRANSACTIONS ON ELECTRON DEVICES
(2017)
Article
Engineering, Electrical & Electronic
Ahmed Kamal Reza, Kaushik Roy
IEEE TRANSACTIONS ON ELECTRON DEVICES
(2019)
Article
Physics, Applied
Ahmed Kamal Reza, Kaushik Roy
JOURNAL OF APPLIED PHYSICS
(2019)