Article
Multidisciplinary Sciences
Lukasz Frackowiak, Feliks Stobiecki, Gabriel David Chaves-O'Flynn, Maciej Urbaniak, Marek Schmidt, Michal Matczak, Andrzej Maziewski, Meike Reginka, Arno Ehresmann, Piotr Kuswik
Summary: Recent research has shown that characteristic features of Tb/Co ferrimagnetic multilayers can be controlled through He+ ion bombardment. Different types of lattices, one with domain walls and one without, have been created with distinctive magnetization reversal behavior. Studies indicate that magnetization reversal occurs through domain wall propagation, regardless of the relative sign of effective magnetization in separated areas.
SCIENTIFIC REPORTS
(2021)
Article
Materials Science, Multidisciplinary
R. B. Morgunov, A. Bezverkhnii, M. Hehn, J. L. Bello, T. Fache, S. Mangin
Summary: In this study, the impact of the Dzyaloshinskii-Moriya interaction (DMI) on magnetic nuclei expansion in Pt/Co/Ir/Co/Pt perpendicular synthetic ferrimagnets is investigated. The competition of DMI contributions results in an inverted dependence of the double domain wall velocity on the in-plane (IP) magnetic field. The manifestation of macroscopic magnetization reversal accelerated by the applied IP magnetic field highlights the role of DMI-induced ellipticity in magnetic relaxation.
Article
Materials Science, Multidisciplinary
M. T. Islam, M. A. J. Pikul, X. S. Wang
Summary: Finite temperature affects the magnetization reversal induced by DCMWP, causing changes in the controlling parameters and the maximum reversal temperature. Increasing system size can raise the maximum reversal temperature, as the energy barrier induced by anisotropy increases with system volume.
JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS
(2021)
Article
Physics, Applied
Yoshiaki Saito, Shoji Ikeda, Tetsuo Endoh
Summary: The study investigated interlayer exchange coupling in Pt/Ru/Pt and Pt/Ru multilayers as potential nonmagnetic spacer layers in synthetic antiferromagnetic (AF) structures. The presence of oscillation periods in AF interlayer exchange coupling was observed, providing insights for systematic study of spin-orbit torque (SOT) in AF structures. Different oscillation periods were found in AF interlayer exchange coupling depending on the type of spacer layers used.
APPLIED PHYSICS LETTERS
(2021)
Article
Materials Science, Multidisciplinary
Yoshiaki Saito, Shoji Ikeda, Tetsuo Endoh
Summary: Investigation on spin-orbit torque in synthetic antiferromagnetic structures reveals higher spin-torque efficiency in stack systems with Pt/Ir/Pt spacer layer. This finding contributes to the improvement of magnetic memory device performance.
Article
Physics, Multidisciplinary
Jing Liu, Caiyin You, Li Ma, Yun Li, Ling Ma, Na Tian
Summary: In this study, Pd/CoZr/MgO thin films with large perpendicular magnetic anisotropy were successfully prepared, and a method of reducing the critical current density with a low out-of-plane magnetic field was demonstrated. The magnetization reversal is a result of the combined effect of the out-of-plane magnetic field and the current-induced spin-orbital torque, and it is highly relevant to the temperature, with higher efficiency at low temperatures.
Article
Nanoscience & Nanotechnology
Satoru Yoshimura, Naoya Oshita, Genta Egawa, Munusamy Kuppan
Summary: A multilayer structure consisting of a high-quality (Bi,La)(Fe,Co)O-3 multiferroic thin film and [Co/Pd] perpendicular magnetic thin film dots was used to demonstrate magnetization reversal of [Co/Pd] dots under an applied electric field. The results showed that the magnetization direction of the [Co/Pd] dots was transferred through the magnetization reversal of the (Bi,La)(Fe,Co)O-3 layer under a local electric field. This demonstration could potentially lead to the development of high-performance magnetic devices with low power consumption, such as large capacity memory.
Article
Multidisciplinary Sciences
Fen Xue, Shy-Jay Lin, Mingyuan Song, William Hwang, Christoph Klewe, Chien-Min Lee, Emrah Turgut, Padraic Shafer, Arturas Vailionis, Yen-Lin Huang, Wilman Tsai, Xinyu Bao, Shan X. X. Wang
Summary: Xue et al. investigate 'type-x' spin-orbit torque switching in Platinum/Cobalt multilayers, demonstrating unique spin polarizations and field-free magnetization switching. The unconventional spin currents result from the strong orbital magnetic moment observed in the low-dimensional Co films. Their work provides additional pathways for electrical control of spintronic devices in pursuit of high-speed, high-density, and low-energy non-volatile memory.
NATURE COMMUNICATIONS
(2023)
Article
Engineering, Electrical & Electronic
W. Chen, Z. Tang, A. Kaizu, S. Kawasaki, T. Roppongi, Y. Wu, M. M. Dovek
Summary: To increase the areal densities of hard disk drives, spin torque devices have been proposed to facilitate magnetic layer reversal. The total flipped magnetic moment under a specific current density needs to be considered during the reversal process. Layers with a low product of magnetization density and thickness can be easily flipped under low current densities, while higher product values have better potential for improving areal density capability, but require higher current densities.
IEEE TRANSACTIONS ON MAGNETICS
(2022)
Article
Materials Science, Multidisciplinary
Yu N. Khaydukov, D. Lenk, V Zdravkov, R. Morari, T. Keller, A. S. Sidorenko, L. R. Tagirov, R. Tidecks, S. Horn, B. Keimer
Summary: The magnetic state of CoO/Co bilayers with different thicknesses was studied using polarized neutron reflectometry, showing a decrease in spin-flip scattering intensity with increased Co layer thickness. Unconventional asymmetry in scattering channels was observed, possibly due to the presence of out-of-plane magnetic stray fields generated by chiral Bloch domain walls. The observations could be useful for designing spintronic devices based on the exchange bias effect.
Article
Physics, Applied
Syuta Honda, Yoshiaki Sonobe
Summary: This study proposes a new method for magnetization reversal on long pillars using both spin-orbit torque (SOT) and spin transfer torque, without the need for spin injection from a ferromagnet. Micromagnetic simulation confirms that this SOT-assisted method significantly reduces the reversal time and successfully reverses pillars with different characteristics. These findings are innovative and significant for practical applications.
JOURNAL OF PHYSICS D-APPLIED PHYSICS
(2022)
Article
Materials Science, Multidisciplinary
S. Al Risi, R. Sbiaa
Summary: Investigation of multilayers consisting of [Co/Ni(tNi)/Co/Pt](x4) with varying Ni insertion layer thicknesses revealed that they exhibit perpendicular magnetic anisotropy. Compared to (Co/Ni)(x8) multilayers, the nucleation field and magnetic coercivity of [Co/Ni(t)/Co/Pt](x4) multilayers were found to be lower and decreased with Ni thickness. The insertion of very thin Ni in (Co/Pt) multilayers provides a way to optimize magnetic properties and adjust domain size for nanowire-based devices.
CURRENT APPLIED PHYSICS
(2022)
Article
Materials Science, Multidisciplinary
Keita Ito, Naoto Kikuchi, Takeshi Seki, Koki Takanashi
Summary: This paper investigates the growth conditions of hcp stacked CoNi films with large magnetic anisotropy and low damping constant. The results show that the formation of hcp-CoNi is promoted near the Ru layer with hcp structure, and low growth temperature and small repetition number increase the volume fraction of hcp phase. The multilayers grown at room temperature exhibit high magnetic anisotropy energy and perpendicular magnetization.
JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS
(2022)
Article
Materials Science, Multidisciplinary
Jun-jie Guo, Qing-lin Xia, Xi-guang Wang, Yao-zhuang Nie, Rui Xiong, Guang-hua Guo
Summary: The study investigates the magnetization reversal of 2D layered material Fe3GeTe2 and finds that the reversal process is temperature and thickness dependent. The competition between long-range magnetic dipolar interaction and perpendicular magnetic anisotropy affects the magnetization reversal process. The results provide important reference for designing Fe3GeTe2-based spintronic devices.
JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS
(2021)
Article
Engineering, Environmental
Dawei Yao, Rojin Feizie Ilmasani, Johann C. Wurzenberger, Thomas Glatz, Joonsoo Han, Aiyong Wang, Derek Creaser, Louise Olsson
Summary: The study illustrates a CO-assisted mechanism for passive NOx adsorption (PNA) by combining experimental and kinetic modeling studies. Pd/SSZ-13 was used as a PNA to control NOx emissions during cold start periods, with the effect of varying gas compositions evaluated. It was found that CO reduces Pd(II) species to Pd(I)/Pd(0) species, increasing the stability of stored NOx species.
CHEMICAL ENGINEERING JOURNAL
(2022)
Article
Physics, Multidisciplinary
Genki Okano, Mamoru Matsuo, Yuichi Ohnuma, Sadamichi Maekawa, Yukio Nozaki
PHYSICAL REVIEW LETTERS
(2019)
Article
Physics, Multidisciplinary
Kazuki Matsuo, Naoki Higashi, Natsumi Iwata, Shohei Sakata, Seungho Lee, Tomoyuki Johzaki, Hiroshi Sawada, Yuki Iwasa, King Fai Farley Law, Hiroki Morita, Yugo Ochiai, Sadaoki Kojima, Yuki Abe, Masayasu Hata, Takayoshi Sano, Hideo Nagatomo, Atsushi Sunahara, Alessio Morace, Akifumi Yogo, Mitsuo Nakai, Hitoshi Sakagami, Tetsuo Ozaki, Kohei Yamanoi, Takayoshi Norimatsu, Yoshiki Nakata, Shigeki Tokita, Junji Kawanaka, Hiroyuki Shiraga, Kunioki Mima, Hiroshi Azechi, Ryosuke Kodama, Yasunobu Arikawa, Yasuhiko Sentoku, Shinsuke Fujioka
PHYSICAL REVIEW LETTERS
(2020)
Article
Physics, Multidisciplinary
Yuki Kurimune, Mamoru Matsuo, Yukio Nozaki
PHYSICAL REVIEW LETTERS
(2020)
Article
Physics, Applied
Shoma Tateno, Yukio Nozaki
PHYSICAL REVIEW APPLIED
(2020)
Article
Materials Science, Multidisciplinary
Taisuke Horaguchi, Mamoru Matsuo, Yukio Nozaki
JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS
(2020)
Article
Optics
A. Iwasaki, D. Nishikawa, M. Okano, S. Tateno, K. Yamanoi, Y. Nozaki, S. Watanabe, S. Watanabe
Summary: We demonstrate a dual-comb vibrometer that achieves high-precision surface vibration measurement by splitting the pulses of one frequency-comb into pulse pairs and utilizing a modified Sagnac geometry to cancel out the introduced delay.
Article
Nanoscience & Nanotechnology
Jieyuan Song, Cong He, Thomas Scheike, Zhenchao Wen, Hiroaki Sukegawa, Tadakatsu Ohkubo, Yukio Nozaki, Seiji Mitani
Summary: In this work, fully epitaxial Ru/Cu heterostructures were fabricated with interface engineering and nanolayer insertions. The atomically controlled interface was confirmed by high-resolution scanning transmission electron microscopy, and the spin current generation and efficiency were evaluated. The results show that the insertion of Cu/Ru nanolayers improves the spin Hall efficiency, and a large effective spin Hall conductivity is achieved in the epitaxial Ru/Cu hybrid nanolayers.
Article
Materials Science, Multidisciplinary
Hayato Nakayama, Taisuke Horaguchi, Cong He, Hiroaki Sukegawa, Tadakatsu Ohkubo, Seiji Mitani, Kazuto Yamanoi, Yukio Nozaki
Summary: We demonstrate spin-torque generation using a compositional gradient at the interface of titanium and tungsten thin films. By varying the width of the compositional gradient interface (CGI) between films, spin-torque ferromagnetic resonance is observed in a ferromagnetic alloy. The width dependence of the spin torque is associated with the generation of spin and/or orbital angular momentum flow at the CGI.
Article
Materials Science, Multidisciplinary
Kazuto Yamanoi, Hikari Semizu, Yukio Nozaki
Summary: This Letter demonstrates the enhancement of the unidirectional spin Hall magnetoresistance (USMR) effect by reducing the Curie temperature TC of the ferromagnetic (FM) layer in a FM/platinum bilayer. The USMR ratio is maximized when the thickness of each FM layer is consistent with the spin diffusion length. By replacing Ni81Fe19 with Ni85Cu15 as the FM material, the maximum USMR ratio can be doubled. This enhancement of the USMR effect is attributed to an increase of electron-magnon scattering in accordance with Bloch law. The use of ferromagnets with face-centered-cubic structures, such as Ni, Ni81Fe19, and Ni85Cu15, increases the USMR effect compared to body-centered-cubic Fe.
Article
Materials Science, Multidisciplinary
Shoma Tateno, Yuki Kurimune, Mamoru Matsuo, Kazuto Yamanoi, Yukio Nozaki
Summary: The study demonstrates the phase shift of the Rayleigh-type surface acoustic wave (RSAW) in a ferromagnetic Ni81Fe19 film based on the gyromagnetic Einstein-de Haas (EdH) torque, which can be significantly enhanced by increasing frequency and provides a new pathway for controlling spin-mechatronics devices.
Article
Materials Science, Multidisciplinary
Yuki Kurimune, Mamoru Matsuo, Sadamichi Maekawa, Yukio Nozaki
Article
Materials Science, Multidisciplinary
Shoma Tateno, Genki Okano, Mamoru Matsuo, Yukio Nozaki
Article
Materials Science, Multidisciplinary
Genki Okano, Yukio Nozaki
Article
Materials Science, Multidisciplinary
Taisuke Horaguchi, Tomoki Tanazawa, Yukio Nozaki
Article
Materials Science, Multidisciplinary
Genki Okano, Yukio Nozaki
