Article
Materials Science, Multidisciplinary
X. D. He, L. L. Zhang, G. J. Wu, J. W. Gao, P. Ran, Muhammad Sajjad, X. W. Zhou, J. W. Cao, L. Xi, YL. Zuo, Y. Ren
Summary: This study systematically investigates the magnetization precession processes of post-prepared and after-annealing Pt buffered [Co/Ni]n multilayers with adjustable perpendicular magnetic anisotropy (PMA) using time-resolved magneto-optical Kerr effect. The findings reveal a linear proportionality between the intrinsic damping constant alpha 0 and the uniaxial magnetic anisotropy Ku, as well as non-monotonic behavior in Ku with increasing Pt thickness tPt. Additionally, it is observed that alpha 0 shows a nonlinear positive correlation with Ku, suggesting that spin-orbit coupling is not the only factor affecting the damping process.
JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS
(2021)
Article
Chemistry, Physical
Garima Vashisht, Utkarsh Shashank, Surbhi Gupta, Rohit Medwal, C. L. Dong, C. L. Chen, K. Asokan, Y. Fukuma, S. Annapoorni
Summary: FeCo was found to inhibit the crystalline growth of FePt and exhibit soft ferromagnetic in-plane behavior with defect-driven hard ferromagnetic properties in the out-plane configuration. Only FePt showed an out-plane magnetization component in FeCo/FePt/Si, and the local coordination of Co remained similar regardless of stack order, while the local geometry of Fe varied due to different crystallinity of FePt in the two series.
JOURNAL OF ALLOYS AND COMPOUNDS
(2021)
Article
Engineering, Electrical & Electronic
A. Sakoguchi, D. Oshima, S. Iwata, T. Kato
Summary: The electric field modulation of PMA and magnetization dynamics in MgO/Co/Pt trilayers was investigated using TRMOKE. The results showed that the PMA and α were both influenced by the electric field. Similar effects were observed in trilayers with MgO(111)/fcc-Co interface.
IEEE TRANSACTIONS ON MAGNETICS
(2022)
Article
Physics, Multidisciplinary
Chunjie Yan, Lina Chen, Kaiyuan Zhou, Liupeng Yang, Qingwei Fu, Wenqiang Wang, Wen-Cheng Yue, Like Liang, Zui Tao, Jun Du, Yong-Lei Wang, Ronghua Liu
Summary: We systematically investigated the influence of Ni and Co thickness on the properties of multilayer films and found the relationship between PMA coefficient, magnetic domain structures, and magnetization dynamics. The results of this study are of great significance for promoting the application of PMA [Co/Ni] multilayer films in spintronic and spin-orbitronic devices.
Article
Materials Science, Multidisciplinary
B. Brahma, R. Hussain, Aakansha, Pratap Behera, S. Ravi, R. Brahma, S. K. Srivastava
Summary: The Co/Ni multilayers thin films prepared under different conditions show varying levels of perpendicular magnetic anisotropy (PMA). Films with Cu underlayer, in-situ annealing, and in-situ combined with post-annealing exhibit enhanced effective PMA constant values, leading to improved magnetic properties. The magnetization reversal in these films is achieved by domain wall propagation.
Article
Multidisciplinary Sciences
Xin Yu Zheng, Sanyum Channa, Lauren J. Riddiford, Jacob J. Wisser, Krishnamurthy Mahalingam, Cynthia T. Bowers, Michael E. McConney, Alpha T. N'Diaye, Arturas Vailionis, Egecan Cogulu, Haowen Ren, Zbigniew Galazka, Andrew D. Kent, Yuri Suzuki
Summary: This study introduces a ferromagnetic insulator spinel, Li0.5Al1.0Fe1.5O4 (LAFO), with low magnetic damping, perpendicular magnetic anisotropy, and no magnetic dead layer. By integrating these LAFO films with epitaxial Pt spin source layers, record low magnetization switching currents and high spin-orbit torque efficiencies are achieved.
NATURE COMMUNICATIONS
(2023)
Article
Chemistry, Multidisciplinary
Lakhan Bainsla, Akash Kumar, Ahmad A. Awad, Chunlei Wang, Mohammad Zahedinejad, Nilamani Behera, Himanshu Fulara, Roman Khymyn, Afshin Houshang, Jonas Weissenrieder, Johan Akerman
Summary: This study investigates the characteristics of ultrathin ferrimagnetic films, and for the first time, observes nearly compensated behavior in 2 nm thick Gd-x(Fe87.5Co12.5)(1-x) films, showing great potential for the development of ultrafast and energy efficient ferrimagnetic spintronic devices.
ADVANCED FUNCTIONAL MATERIALS
(2022)
Article
Nanoscience & Nanotechnology
James Lourembam, Khoong Hong Khoo, Jinjun Qiu, Huiqing Xie, Seng Kai Wong, Qi Jia Yap, Sze Ter Lim
Summary: Nanometer-thick Co-Fe-B/MgO based structures show reduced Gilbert damping, making them promising for next-generation ultra-low-power MRAM devices.
ADVANCED ELECTRONIC MATERIALS
(2021)
Article
Chemistry, Multidisciplinary
Mengchao Li, Huali Yang, Yali Xie, Kai Huang, Lili Pan, Wei Tang, Xilai Bao, Yumeng Yang, Jie Sun, Xinming Wang, Shenglei Che, Run-Wei Li
Summary: The magnetic properties of flexible magnetic films are sensitive to mechanical stress due to magnetoelastic coupling, which affects the performance of flexible magnetoelectronic devices. We demonstrate that stacking different materials in multilayers can enhance the stress stability of the magnetic properties. The strength of magnetoelastic anisotropy and the initial effective magnetic anisotropy play significant roles in determining the stress stability of the film.
Article
Physics, Applied
Keisuke Yamada, Shun-ichi Takamatsu, Hiroki Asakawa, Yoshinobu Nakatani
Summary: This study reports current-induced magnetization switching in a perpendicularly magnetized nanomagnet under specific conditions and investigates the influencing factors. The results demonstrate that the magnetization switching can be reduced under certain conditions, which is of great significance for exploring the characteristics of nanomagnets.
APPLIED PHYSICS EXPRESS
(2023)
Article
Chemistry, Physical
Young Chan Won, Sang Ho Lim
Summary: The study investigates the perpendicular magnetic anisotropy and crystalline structure of Ta/NiFeB/MgO stacks. Annealing induces PMA and increases magnetic moment, with the thinnest 0.5-nm Ta layer showing the strongest PMA at 400 degrees Celsius. X-ray diffraction confirms the formation of NiFe (001) phase essential for high tunneling magnetoresistance ratio.
JOURNAL OF ALLOYS AND COMPOUNDS
(2021)
Article
Physics, Applied
Ryoya Hiramatsu, Daisuke Miura, Akimasa Sakuma
Summary: In this study, we propose a method for calculating the Gilbert damping constants at finite temperature and apply it to two materials. By comparing our calculated results with experimental values, we observe a discrepancy, which reflects the characteristics of the torque correlation model.
APPLIED PHYSICS EXPRESS
(2022)
Article
Nanoscience & Nanotechnology
Zhen Liu, Yongzheng Guo, Zhiyong Chen, Tao Gong, Yue Li, Yuting Niu, Yingchun Cheng, Haipeng Lu, Longjiang Deng, Bo Peng
Summary: This study reveals the intrinsic structure of few-layer CrI3 and its correlation with magnetic orders, potentially opening up opportunities for creating magnetic textures through stacking design.
Article
Chemistry, Physical
Wei Du, Mengli Liu, Guocai Wang, Hua Su, Bo Liu, Hao Meng, Xiaoli Tang
Summary: This research investigates the properties of Pt/CoFeB/MgO (bottom structure) and MgO/CoFeB/Pt (top structure) samples with different compositions. It is found that the bottom structure always exhibits stronger perpendicular magnetic anisotropy (PMA) properties compared to the top structure. Additionally, a higher Co atomic composition in CoFeB leads to a stronger PMA. The results are attributed to the Pt-Co hybridization and the catalytic action of Pt on the Fe-O hybridization at the CoFeB/MgO interface.
JOURNAL OF ALLOYS AND COMPOUNDS
(2022)
Article
Nanoscience & Nanotechnology
T. Usami, M. Itoh, T. Taniyama
Summary: Antiferromagnetic materials are of interest for device applications due to their lack of stray field and high-frequency response. Understanding the interfacial effects between antiferromagnetic and ferromagnetic materials, particularly magnetization dynamics and magnetic damping, is crucial for integrating them into magnetic devices. By studying the B2-ordered FeRh with a first-order phase transition from antiferromagnetic to ferromagnetic states, researchers can gain insight into the dynamic properties at the interface, such as the temperature dependence of the effective Gilbert damping constant.
Article
Multidisciplinary Sciences
Sascha Brinker, Felix Kuester, Stuart S. P. Parkin, Paolo Sessi, Samir Lounis
Summary: High-energy resolution spectroscopic studies play a significant role in accessing magnetodynamics quantities for quantum magnets. In this study, researchers investigate a new type of low-energy spin excitations for quantum spins coupled to an electron bath. By combining time-dependent and many-body perturbation theories, they explain the magnetic field-dependent tunneling spectra as a result of an interplay between weak magnetic anisotropy energy, magnetic interactions, and Stoner-like electron-hole excitations. The results provide insights into noncollinear magnetic ground states and the dominance of ferro- and antiferromagnetic interactions.
Article
Multidisciplinary Sciences
Panagiotis Ch Filippou, Sergey Faleev, Chirag Garg, Jaewoo Jeong, Yari Ferrante, Teya Topuria, Mahesh G. Samant, Stuart S. P. Parkin
Summary: The researchers have successfully synthesized ultrathin ordered synthetic antiferromagnetic structures by combining atomically ordered RuAl layers and perpendicularly magnetized Heusler layers, expanding the range of synthetic antiferromagnets and magnetic compounds for spintronic technologies.
Article
Chemistry, Multidisciplinary
Hyeon Han, Hua Zhou, Charles Guillemard, Manuel Valvidares, Arpit Sharma, Yan Li, Ankit K. Sharma, Ilya Kostanovskiy, Arthur Ernst, Stuart S. P. Parkin
Summary: This study uses the hydrogen spillover method to tailor the properties of SrRuO3 thin films by incorporating hydrogen. It is found that the magnetization and Curie temperature of the films are significantly reduced, and the structure evolves from an orthorhombic to a tetragonal phase with increasing hydrogen content. In situ crystal truncation rod measurements show that the structural phase transition is related to tilting of the RuO6 octahedral units. Density functional theory analysis demonstrates that the significant changes in magnetization result from shifts in the Fermi level. These findings provide new insights into the physical properties of SrRuO3 through the modulation of its lattice symmetry and emergent physical phenomena using the hydrogen spillover technique.
ADVANCED MATERIALS
(2023)
Article
Nanoscience & Nanotechnology
Jiho Yoon, See-Hun Yang, Jae-Chun Jeon, Andrea Migliorini, Ilya Kostanovskiy, Tianping Ma, Stuart S. P. Parkin
Summary: This study demonstrates that chiral domain walls in synthetic antiferromagnet-ferromagnet lateral junction have high stability against large magnetic fields and can be efficiently moved across the junction by current. The approach takes advantage of field-induced global energy barriers in the unique energy landscape of the junction to overcome the trade-off between energy efficiency and thermal stability. The research also shows that thermal fluctuations increase the energy barrier and further stabilize the domain wall in the junction at higher temperatures.
NATURE NANOTECHNOLOGY
(2022)
Article
Physics, Condensed Matter
Sergey V. Faleev, Panagiotis Ch. Filippou, Chirag Garg, Jaewoo Jeong, Mahesh G. Samant, Stuart S. P. Parkin
Summary: This article proposes a mechanism for thin films made of Heusler compounds to simultaneously have perpendicular magnetic anisotropy (PMA) and be half-metallic. It is suggested that the thin film can undergo a tetragonal distortion by adopting the lattice constant of the underlayer material during deposition. The distortion can be tuned by using underlayer materials with different in-plane lattice constants, optimizing it to provide sufficient PMA while retaining the half-metallic properties of the Heusler compound.
PHYSICA STATUS SOLIDI B-BASIC SOLID STATE PHYSICS
(2023)
Article
Chemistry, Multidisciplinary
Durgesh Kumar, Hong Jing Chung, JianPeng Chan, Tianli Jin, Sze Ter Lim, Stuart S. P. Parkin, Rachid Sbiaa, S. N. Piramanayagam
Summary: Neuromorphic computing is a potential technology for low power intelligent devices. Spintronics-based neurons and synapses have higher endurance. By engineering the beta-W spin-orbit coupling material, we achieved low energy domain wall motion. The energy consumption for moving the domain wall is 27 aJ/bit, showing the potential for ultralow energy spin-based neuromorphic elements.
Article
Physics, Applied
S. Miki, K. Hashimoto, J. Cho, J. Jung, C. Y. You, R. Ishikawa, E. Tamura, H. Nomura, M. Goto, Y. Suzuki
Summary: In this study, a technique was developed to fabricate a suitable potential landscape in magnetic films for the diffusion of information carriers. Irradiation with focused ion beams was found to shift the critical temperature of magnetic skyrmions. The effects of ion implantation on the film were analyzed using TOF-SIMS and AFM.
APPLIED PHYSICS LETTERS
(2023)
Article
Chemistry, Multidisciplinary
Glenn Wagner, Souvik Das, Johannes Jung, Artem Odobesko, Felix Kuester, Florian Keller, Jedrzej Korczak, Andrzej Szczerbakow, Tomasz Story, Stuart S. P. Parkin, Ronny Thomale, Titus Neupert, Matthias Bode, Paolo Sessi
Summary: Step edges of topological crystalline insulators in Pb1-xSnxSe were studied using scanning tunneling microscopy and spectroscopy. When the energy position of the step edge approaches the Fermi level, a correlation gap opens up. The experimental results suggest that the interaction effects are enhanced due to the collapsing of electronic density into a one-dimensional channel, providing a unique system to study the intertwining of topology and many-body electronic effects. Theoretical modeling was performed through a Hartree-Fock analysis.
Article
Nanoscience & Nanotechnology
Kun-Rok Jeon, Binoy Krishna Hazra, Jae-Keun Kim, Jae-Chun Jeon, Hyeon Han, Holger L. Meyerheim, Takis Kontos, Audrey Cottet, Stuart S. P. Parkin
Summary: This study reports the spin-triplet supercurrent spin valves in chiral antiferromagnetic Josephson junctions and a direct-current superconducting quantum interference device. By utilizing the Berry curvature-induced fictitious magnetic fields and the non-collinear atomic-scale spin arrangement, long-range triplet Cooper pairing is achieved in the chiral antiferromagnet Mn3Ge. The observed supercurrent spin-valve behaviors under a small magnetic field and the direct-current superconducting quantum interference device functionality are theoretically verified.
NATURE NANOTECHNOLOGY
(2023)
Article
Physics, Applied
Stephanie M. Bohaichuk, Suhas Kumar, Mahnaz Islam, Miguel Munoz Rojo, R. Stanley Williams, Gregory Pitner, Jaewoo Jeong, Mahesh G. Samant, Stuart S. P. Parkin, Eric Pop
Summary: Oscillatory devices are important in biomimetic neuronal spiking computing systems, but understanding their time scales is challenging due to the influence of external circuitry. In this study, we demonstrate the challenges using a sub-100-nm VO2 Mott oscillator with a nanogap cut in a metallic carbon nanotube electrode. Despite its nanoscale thermal volume, external parasitics result in orders-of-magnitude slower dynamics. We discuss methods for determining when measurements are dominated by extrinsic factors and the conditions for observing intrinsic oscillation frequencies.
PHYSICAL REVIEW APPLIED
(2023)
Article
Physics, Multidisciplinary
Martina O. Soldini, Felix Kuester, Glenn Wagner, Souvik Das, Amal Aldarawsheh, Ronny Thomale, Samir Lounis, Stuart S. P. Parkin, Paolo Sessi, Titus Neupert
Summary: Scientists have extended the idea of the one-dimensional magnetic adatom chain structure to two-dimensional systems, which may host topological states. By placing magnetic adatoms on the surface of a conventional superconductor, lattices of Yu-Shiba-Rusinov bound states can be formed to create topological bands within the superconducting gap.
Article
Multidisciplinary Sciences
G. Poelchen, J. Hellwig, M. Peters, D. Yu. Usachov, K. Kliemt, C. Laubschat, P. M. Echenique, E. V. Chulkov, C. Krellner, S. S. P. Parkin, D. V. Vyalikh, A. Ernst, K. Kummer
Summary: The metallic antiferromagnet CeCo2P2 exhibits long-lived spin-waves at terahertz frequencies, suggesting the potential use of metallic antiferromagnets for spin-wave information processing.
NATURE COMMUNICATIONS
(2023)
Article
Multidisciplinary Sciences
Yaojia Wang, Shuo-Ying Yang, Pranava K. Sivakumar, Brenden R. Ortiz, Samuel M. L. Teicher, Heng Wu, Abhay K. Srivastava, Chirag Garg, Defa Liu, Stuart S. P. Parkin, Eric S. Toberer, Tyrel McQueen, Stephen D. Wilson, Mazhar N. Ali
Summary: Materials with Kagome nets, such as K1-xV3Sb5, show potential in exploring unconventional superconductivity and Josephson devices. In this study, Josephson junctions of K1-xV3Sb5 were fabricated, leading to the observation of magnetic field-dependent magnetoresistance and anisotropic interference patterns. An anisotropic internal magnetic field in K1-xV3Sb5 and spatially localized conducting channels arising from edge states were also observed, suggesting the presence of spin-triplet superconductivity and providing new insights for research on unconventional superconductivity and Josephson devices based on Kagome metals.
Article
Materials Science, Multidisciplinary
Eunchong Baek, Suhyeok An, Soobeom Lee, Dongryul Kim, Jun-Su Kim, Ki-Seung Lee, Chun-Yeol You
Summary: We investigated the electric control of antiferromagnetic ordering in Pt/Co/IrMn heterostructures through assist magnetic field. Experimental results with different directions and amplitudes of the assist magnetic field demonstrated the magnetic coupling between ferromagnet and antiferromagnet spins. Furthermore, we found that the magnitude and direction of exchange bias can be manipulated by the magnitude of the current pulse. The observed phenomena can be explained by a numerical macrospin model, indicating the excitation and precession of antiferromagnetic spins mediated by magnetic coupling with the ferromagnet.
Article
Chemistry, Multidisciplinary
Durgesh Kumar, Hong Jing Chung, JianPeng Chan, Tianli Jin, Sze Ter Lim, Stuart S. P. Parkin, Rachid Sbiaa, S. N. Piramanayagam
Summary: Neuromorphic computing is a potential technology for low-power intelligent devices. Spintronics-based neurons and synapses have higher endurance, but low-energy domain wall devices are preferred for low-power devices. By engineering the beta-W spin-orbit coupling material, we achieve low-current density DW motion with ultralow energy consumption and current density reduction.
