Article
Materials Science, Multidisciplinary
Jongpil Yun, Se Kwon Kim
Summary: The existing proposals for superfluidlike spin transport have been limited to easy-plane magnets, but in this work, we show that superfluidlike spin transport can also be realized based on easy-axis magnets. We find that by applying a spin torque, a nonequilibrium easy-cone state can be engendered in easy-axis magnets, breaking the U(1) spin-rotational symmetry and enabling superfluidlike spin transport. Using micromagnetic simulations, we confirm the theoretical prediction and demonstrate the potential of dynamic states of magnets for studying spin-transport phenomena.
Article
Engineering, Electrical & Electronic
Jeongchun Ryu, Ryan Thompson, Jae Yeol Park, Seok-Jong Kim, Gaeun Choi, Jaimin Kang, Han Beom Jeong, Makoto Kohda, Jong Min Yuk, Junsaku Nitta, Kyung-Jin Lee, Byong-Guk Park
Summary: Spin-orbit coupling converts charge current into spin current, generating spin-orbit torque. Previous studies only used part of the polarization of the spin current, while this study demonstrates a method that utilizes all three polarizations. This approach reduces the switching current for field-free spin-orbit torque and is applicable for mass production.
NATURE ELECTRONICS
(2022)
Article
Chemistry, Multidisciplinary
Sambit Ghosh, Taro Komori, Ali Hallal, Jose Pena Garcia, Toshiki Gushi, Taku Hirose, Haruka Mitarai, Hanako Okuno, Jan Vogel, Mairbek Chshiev, Jean-Philippe Attane, Laurent Vila, Takashi Suemasu, Stefania Pizzini
Summary: This study investigates the spin-transfer torque-driven domain wall motion in ferrimagnetic manganese nickel nitride films, where fine adjustment of nickel content can achieve magnetization and angular momentum compensation. Large domain wall velocities, approaching 3000 m/s, are measured near the angular momentum compensation point, offering insights for the development of new magnetic memories and logic devices. The reversal of domain wall motion direction, observed when crossing the compensation composition, is related to the change in angular momentum direction with respect to spin polarization, as confirmed by ab initio band structure calculations.
Article
Chemistry, Multidisciplinary
Sina Mayr, Lukas Flajsman, Simone Finizio, Ales Hrabec, Markus Weigand, Johannes Forster, Hermann Stoll, Laura J. Heyderman, Michal Urbanek, Sebastian Wintz, Jorg Raabe
Summary: The influence of a static in-plane magnetic field on the emission of nanoscale spin waves from magnetic vortex cores is studied in disk structures of synthetic ferrimagnets and single ferromagnetic layers. Increasing magnetic bias field displaces the wave-emitting vortex core from the center of the disk toward its edge without altering the spin-wave dispersion relation noticeably. At higher magnetic fields, anisotropic lateral expansion of the core occurs in single-layer disks leading to directional emission and propagation of waves.
Article
Engineering, Electrical & Electronic
E. Raymenants, O. Bultynck, D. Wan, T. Devolder, K. Garello, L. Souriau, A. Thiam, D. Tsvetanova, Y. Canvel, D. E. Nikonov, I. A. Young, M. Heyns, B. Soree, I. Asselberghs, I. Radu, S. Couet, V. D. Nguyen
Summary: In this study, domain wall devices based on perpendicular magnetic tunnel junctions with a hybrid free layer design were developed to achieve electrical read and write, as well as fast domain wall motion driven via spin-orbit torque. The devices showed good performance in terms of tunnelling magnetoresistance readout, spin-transfer torque writing, and domain wall depinning efficiency. Overall, the domain wall conduit based on a synthetic antiferromagnet demonstrated potential for reliable domain wall motion and faster write speed compared to a device based on Pt/Co.
NATURE ELECTRONICS
(2021)
Article
Materials Science, Multidisciplinary
Ting-Ting Liu, Yi-Fei Hu, Yang Liu, Zhe-Jun-Yu Jin, Zheng-Hua Tang, Ming-Hui Qin
Summary: In this study, the domain wall motion in ferrimagnets driven by a circularly polarized magnetic field was investigated using the collective coordinate theory and atomistic micromagnetic simulations. The effect of the Dzyaloshinskii-Moriya interaction (DMI) was particularly studied. The results showed that the ferrimagnetic wall moved at a speed linearly dependent on the magnitude of DMI, similar to the case of antiferromagnetic domain wall. Additionally, the DMI was found to modulate the domain wall dynamics in a similar way to the net spin density, providing another internal parameter for controlling the domain wall in ferrimagnets. Moreover, the study demonstrated that the domain wall dynamics in ferrimagnets were much faster than those in ferromagnets, confirming the high potential of ferrimagnets in future spintronic applications.
Article
Physics, Applied
Yuelei Zhao, Sheng Yang, Kai Wu, Xiaoguang Li, Xichao Zhang, Li Li, Zhiqin Chu, Chong Bi, Yan Zhou
Summary: Deterministic switching in synthetic antiferromagnets can be achieved through flexible domain control in the absence of external magnetic fields, addressing the technical challenge of requiring an in-plane magnetic field.
APPLIED PHYSICS LETTERS
(2022)
Article
Chemistry, Physical
Djoudi Ourdani, Mohamed Belmeguenai, Mihai Gabor, Andrey Stashkevich, Yves Roussigne
Summary: In this article, a numerical study is conducted on the stabilization and eigenmodes of the skyrmion chiral spin texture in nanometric dots. The appropriate multilayer structure is identified through experimental characterization, and the eigenfrequency, eigenmode profile, and spectral density are calculated for different dot sizes. The optimal dot size for a feasible experiment is determined.
Article
Materials Science, Multidisciplinary
Munsu Jin, Ik-Sun Hong, Duck-Ho Kim, Kyung-Jin Lee, Se Kwon Kim
Summary: The study investigates the dynamics of a ferrimagnetic domain wall driven by a rotating magnetic field. It identified two regimes based on the frequency of the field, phase-locking and phase-unlocking, which demonstrate different behaviors in domain-wall motion. The work also highlights the significance of studying magnetic solitons under time-varying biases as a platform for exploring critical phenomena.
Article
Materials Science, Multidisciplinary
Massimiliano d'Aquino, Salvatore Perna, Matteo Pancaldi, Riccardo Hertel, Stefano Bonetti, Claudio Serpico
Summary: In this study, we investigate the possibility of exciting ultrashort spin waves in ferromagnetic thin films using time-harmonic electromagnetic fields with terahertz frequency. We consider the inertial Landau-Lifshitz-Gilbert equation and develop an analytical theory for exchange-dominated inertial spin waves. Numerical micromagnetic simulations are performed to verify the theory and provide insights into realistic ultrafast dynamics experiments.
Article
Chemistry, Multidisciplinary
Luka Skoric, Claire Donnelly, Aurelio Hierro-Rodriguez, Miguel A. Cascales Sandoval, Sandra Ruiz-Gomez, Michael Foerster, Miguel A. Nino, Rachid Belkhou, Claas Abert, Dieter Suess, Amalio Fernandez-Pacheco
Summary: This study proposes a three-dimensional magnetic interconnector that utilizes geometry-driven automotion of domain walls for magnetic information transfer between functional magnetic planes. Through experiments and simulations, it is found that large thickness gradients in the structure are the main mechanism for the automotion of domain walls. This work demonstrates a possible mechanism for efficient transfer of magnetic information in three dimensions.
Article
Chemistry, Multidisciplinary
Vladimir Grigorev, Mariia Filianina, Yaryna Lytvynenko, Sergei Sobolev, Amrit Raj Pokharel, Amon P. Lanz, Alexey Sapozhnik, Armin Kleibert, Stanislav Bodnar, Petr Grigorev, Yurii Skourski, Mathias Klaeui, Hans-Joachim Elmers, Martin Jourdan, Jure Demsar
Summary: The absence of stray fields, insensitivity to external magnetic fields, and ultrafast dynamics make antiferromagnets promising candidates for active elements in spintronic devices. Researchers demonstrate successful manipulation of the Neel vector in the metallic collinear antiferromagnet Mn2Au by using strain and femtosecond laser excitation. The aligned state achieved through this method is stable at room temperature and insensitive to magnetic fields, suggesting potential applications in robust high-density memory devices.
Article
Materials Science, Multidisciplinary
Dion M. F. Hartmann, Andreas Rueckriegel, Rembert A. Duine
Summary: In this paper, a theory for nonlocal transport of bound magnons through a ferromagnetic insulator via magnetic domain walls is developed. This framework provides a basis for reconfigurable magnonic devices.
Article
Physics, Applied
Bo Wang, Gaoshuai Wei, Jianing Chen, Li Wang
Summary: This study investigates ultrafast spin polarization in semi-insulating GaAs using terahertz time-domain spectroscopy. The results demonstrate that the transmitted and reflected terahertz signals exhibit different dynamic evolutions under the excitation of different polarization laser pulses, indicating the generation and relaxation process of spin-polarized electrons.
APPLIED PHYSICS LETTERS
(2022)
Article
Materials Science, Multidisciplinary
R. Rama-Eiroa, P. E. Roy, J. M. Gonzalez, K. Y. Guslienko, J. Wunderlich, R. M. Otxoa
Summary: The motion of a Neel-like 180 domain wall in the layered collinear antiferromagnet Mn2Au under the influence of a time-dependent staggered spin-orbit field is studied, revealing that under certain conditions, the motion of the domain wall can be abruptly interrupted by external stimuli and transformed into a complex translational mobility.
JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS
(2022)
Article
Materials Science, Multidisciplinary
Boyao Lyu, Weiwei Wang, Haifeng Du
Summary: The dynamics of a magnetic bibubble driven by a magnetic field gradient were studied, showing that the velocity and skyrmion hall angle depend on the angle between the field gradient and the orientation of the bibubble. Additionally, the bibubble exhibits orbital motion and orientation oscillation in the presence of circular field gradients.
JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS
(2022)
Article
Physics, Applied
Afshin Houshang, Mohammad Zahedinejad, Shreyas Muralidhar, Roman Khymyn, Mona Rajabali, Himanshu Fulara, Ahmad A. Awad, Johan Akerman, Jakub Checinski, Mykola Dvornik
Summary: Ising machines (IMs) are physical systems designed to find solutions to combinatorial optimization problems. In this study, we demonstrate an oscillator-based IM using nanoconstriction spin Hall nano-oscillators. We show that the phase states of the oscillators can solve combinatorial optimization problems and our architecture holds promise for faster sampling, reduced power consumption, and smaller footprint compared to existing technologies.
PHYSICAL REVIEW APPLIED
(2022)
Article
Multidisciplinary Sciences
Weiwei Wang, Dongsheng Song, Wensen Wei, Pengfei Nan, Shilei Zhang, Binghui Ge, Mingliang Tian, Jiadong Zang, Haifeng Du
Summary: Using tailored current pulses, researchers demonstrate the operations of creating, deleting, and driving skyrmions in nanodevices. These results have immediate significance towards the development of skyrmion-based memory or logic devices.
NATURE COMMUNICATIONS
(2022)
Article
Multidisciplinary Sciences
Cyril Leveille, Erick Burgos-Parra, Yanis Sassi, Fernando Ajejas, Valentin Chardonnet, Emanuele Pedersoli, Flavio Capotondi, Giovanni De Ninno, Francesco Maccherozzi, Sarnjeet Dhesi, David M. Burn, Gerrit van der Laan, Oliver S. Latcham, Andrey Shytov, Volodymyr V. Kruglyak, Emmanuelle Jal, Vincent Cros, Jean-Yves Chauleau, Nicolas Reyren, Michel Viret, Nicolas Jaouen
Summary: This study investigates the ultrafast dynamics of chiral domain walls and observes the emergence of a transient spin chiral texture on the walls. The research findings suggest that the spin texture of the domain walls changes shortly after optical pumping.
NATURE COMMUNICATIONS
(2022)
Article
Physics, Applied
Rabiul Islam, Peng Li, Marijan Beg, Manoj Sachdev, Guo-Xing Miao
Summary: In this study, a helimagnet-based emerging memory device design is presented, which can store multiple bits of information per device. The device consists of a helimagnet layer placed between two ferromagnetic layers, allowing specific spin configurations to be locked in. The writing of memory states is simulated by applying an in-plane magnetic field that rotates and transforms the spin configurations of the device. By simply changing the direction of the field, multi-bit data storage per unit memory cell can be achieved.
APPLIED PHYSICS LETTERS
(2023)
Article
Chemistry, Multidisciplinary
Sang Yong Song, Chengyun Hua, Luke Bell, Wonhee Ko, Hans Fangohr, Jiaqiang Yan, Gabor B. Halasz, Eugene F. Dumitrescu, Benjamin J. Lawrie, Petro Maksymovych
Summary: New pathways are needed to control the morphology and dynamics of superconducting vortex lattices in order to transform them into a computing platform. It has been discovered that nematic twin boundaries can align superconducting vortices in adjacent terraces. Different structural phases of the vortex lattice can be assumed by varying the density and morphology of the twin boundaries. These findings have implications for the design and control of strain-based topological quantum computing architectures.
Article
Multidisciplinary Sciences
Martin Lang, Marijan Beg, Ondrej Hovorka, Hans Fangohr
Summary: Complex magnetic materials hosting topologically non-trivial objects called skyrmions are being extensively studied as they have the potential to revolutionize data storage and processing. Recent research has shown that thin nanodisks composed of layers with opposite chirality can host a single stable Bloch point. Our micromagnetic simulations demonstrate that FeGe nanostrips consisting of two layers with opposite chirality can simultaneously host multiple coexisting Bloch points of different types. The number of Bloch points that can coexist depends on the strip geometry and the individual Bloch point types. Our simulation results enable us to predict strip geometries suitable for different numbers of Bloch points, which we confirm with an example of an 80-Bloch-point configuration.
SCIENTIFIC REPORTS
(2023)
Article
Materials Science, Multidisciplinary
Tobias Lojewski, Mohamed F. Elhanoty, Loic Le Guyader, Oscar Granaes, Naman Agarwal, Christine Boeglin, Robert Carley, Andrea Castoldi, Christian David, Carsten Deiter, Florian Doering, RobinY Engel, Florian Erdinger, Hans Fangohr, Carlo Fiorini, Peter Fischer, Natalia Gerasimova, Rafael Gort, Frank deGroot, Karsten Hansen, Steffen Hauf, David Hickin, Manuel Izquierdo, Benjamin E. Van Kuiken, Yaroslav Kvashnin, Charles-Henri Lambert, David Lomidze, Stefano Maffessanti, Laurent Mercadier, Giuseppe Mercurio, Piter S. Miedema, Katharina Ollefs, Matthias Pace, Matteo Porro, Javad Rezvani, Benedikt Roesner, Nico Rothenbach, Andrey Samartsev, Andreas Scherz, Justina Schlappa, Christian Stamm, Martin Teichmann, Patrik Thunstrom, Monica Turcato, Alexander Yaroslavtsev, Jun Zhu, Martin Beye, Heiko Wende, Uwe Bovensiepen, Olle Eriksson, Andrea Eschenlohr
Summary: By combining femtosecond time-resolved X-ray absorption spectroscopy with ab initio time-dependent density functional theory, we analyze the electronic structure of fcc Ni on a femtosecond time scale. We observe transient broadening and energy shifts in the absorption spectra, which are explained by electron repopulation and correlation-induced modifications of the electronic structure, accounting for the local Coulomb interaction.
MATERIALS RESEARCH LETTERS
(2023)
Article
Physics, Condensed Matter
Long Li, Weiwei Wang, Xitong Xu, Ning Wang, Zhaosheng Wang, Dongsheng Song, Zhe Qu, Haifeng Du
Summary: In this study, we used Lorentz transmission electron microscopy to investigate the influence of magnetic skyrmions on the Hall effect in FeGe under low magnetic fields, as well as examine the magnetoresistance and Hall effect of FeGe under a high magnetic field of 28 T. Our findings reveal different mechanisms governing the magnetoresistance at low and high temperatures, with the anomalous Hall effect playing a significant role at low magnetic fields. Additionally, we demonstrate a transition in the dominant carrier type from electrons to holes as the temperature increases.
JOURNAL OF PHYSICS-CONDENSED MATTER
(2023)
Article
Crystallography
Oleksii Turkot, Fabio Dall'Antonia, Richard J. Bean, Juncheng E, Hans Fangohr, Danilo E. Ferreira de Lima, Sravya Kantamneni, Henry J. Kirkwood, Faisal H. M. Koua, Adrian P. Mancuso, Diogo V. M. Melo, Adam Round, Michael Schuh, Egor Sobolev, Raphael de Wijn, James J. Wrigley, Luca Gelisio
Summary: Researchers have developed a semi-automated pipeline called EXtra-Xwiz to streamline and accelerate the analysis of serial femtosecond crystallography (SFX) data, which is crucial for experiments with high data complexity like the European XFEL.
Article
Materials Science, Multidisciplinary
Lingyao Kong, Jin Tang, Weiwei Wang, Yaodong Wu, Jialiang Jiang, Yihao Wang, Junbo Li, Yimin Xiong, Mingliang Tian, Haifeng Du
Summary: Using Lorentz transmission electronic microscopy magnetic imaging, we directly observed three-dimensional (3D) type-III hybrid bubbles in Fe3Sn2 nanodisks, which consist of Neel-twisted skyrmion bubbles with topological charge Q = -1 in near-surface layers and type-II bubbles with Q = 0 in interior layers. By applying a tilted magnetic field, we demonstrated controlled topological magnetic transformations of the three types of bubbles in a confined ferromagnetic nanodisk. Our observations were well reproduced with micromagnetic simulations based on measured magnetic parameters. This study advances the fundamental classification and understanding of magnetic bubbles, with potential implications for applications of 3D magnetism.
Article
Materials Science, Multidisciplinary
Weiwei Wang, Pengfei Hu, Lingyao Kong, Dongsheng Song, Haifeng Du
Summary: This study investigates the dynamics of magnetic skyrmions in cylindrical nanotubes using numerical and analytical methods. In the absence of external fields, the skyrmion exhibits a helical motion in the nanotube. However, when an external field is applied perpendicular to the nanotube, the skyrmion shows Walker breakdown phenomenon. A steady skyrmion motion is observed in the low current regime, while the skyrmion moves forward and back when the current exceeds a critical density.
Article
Materials Science, Multidisciplinary
Hui Han, Hong Lin, Wei Gan, Ruichun Xiao, Yucheng Liu, Jiefeng Ye, Limin Chen, Weiwei Wang, Lei Zhang, Changjin Zhang, Hui Li
Summary: Manipulation of spin orientation in magnetic material has attracted increasing research interest due to its potential in exploring magnetic interactions and designing electronic devices. We reported the field-induced spin reorientation below Neel temperature in the antiferromagnet MnPS3. The coexistence of ferromagnetic and antiferromagnetic phases in MnPS3 was observed at temperatures below -34K with external magnetic fields in both perpendicular and parallel configurations.
Article
Materials Science, Multidisciplinary
V. A. Gubanov, V. V. Kruglyak, S. E. Sheshukova, V. D. Bessonov, S. A. Nikitov, A. Sadovnikov
Summary: We investigate the propagation of spin waves along a magnonic waveguide by inducing a local decrease in magnetization using a focused laser spot. Utilizing the phase-sensitive Brillouin light scattering technique, we image how the spin waves propagate along the waveguide with a local heat landscape. Experimental results demonstrate frequency-selective signal propagation along the waveguide. Micromagnetic simulations reveal changes in intermodal interference after the heated area. The proposed method of reconfiguring the magnetization landscape has potential applications in magnonic devices with frequency-selective spin wave transport.
