Article
Physics, Multidisciplinary
Wang Ri-Xing, Zeng Yi-Han, Zhao Jing-Li, Li Lian, Xiao Yun-Chang
Summary: The data writing scheme of magnetization reversal driven by spin-transfer torque has become a mainstream way of implementing information writing in magnetic random access memory, overcoming the shortcomings of traditional magnetic-field writing mechanism. However, magnetic random access memories based on this method face issues such as barrier reliability and limited storage speed. Recent experimental studies have shown that the spin-orbit torque through the spin Hall effect or Rashba effect in heavy-metal/ferromagnetic bilayer structures have the potential advantages in overcoming these limitations and achieving rapid reversal.
ACTA PHYSICA SINICA
(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
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
G. Sala, J. Meyer, A. Flechsig, L. Gabriel, P. Gambardella
Summary: We studied the incubation and transition times of magnetization switching in nanomagnets with perpendicular anisotropy induced by spinorbit torques. A phenomenological model was proposed to interpret the dependence of incubation time on voltage pulse amplitude and assisting magnetic field, and the volume of the seed domain triggering the switching was estimated. Our measurements revealed a correlation between incubation and transition times mediated by temperature variation during the electric pulse. Stochastic distributions of the two times were discussed in terms of energy barriers opposing the nucleation and expansion of the seed domain, and two models based on the log-normal and gamma functions were proposed to account for the different origins of incubation and transition time variability.
Article
Multidisciplinary Sciences
Korbinian Baumgaertl, Dirk Grundler
Summary: Spin wave based computing offers advantages of low power consumption and absence of joule heating, but the lack of a direct method for storing spin wave information is a challenge. The authors demonstrate the reversal of nanomagnets using spin waves with small power requirements.
NATURE COMMUNICATIONS
(2023)
Article
Physics, Multidisciplinary
Shutaro Karube, Takahiro Tanaka, Daichi Sugawara, Naohiro Kadoguchi, Makoto Kohda, Junsaku Nitta
Summary: The study investigates the generation of spin-splitter torque in collinear antiferromagnetic RuO2, revealing different spin current polarizations on various crystal planes. By utilizing this spin-splitter torque, field-free switching of ferromagnetic materials can be achieved, contributing to the development of antiferromagnetic spin-orbitronics.
PHYSICAL REVIEW LETTERS
(2022)
Article
Physics, Multidisciplinary
H. Bai, L. Han, X. Y. Feng, Y. J. Zhou, R. X. Su, Q. Wang, L. Y. Liao, W. X. Zhu, X. Z. Chen, F. Pan, X. L. Fan, C. Song
Summary: This article provides experimental evidence of the spin splitting torque (SST) in collinear antiferromagnet RuO2 films, which combines the advantages of conventional spin transfer torque (STT) and spin-orbit torque (SOT) and enables controllable spin polarization. The findings not only expand the research field of spin torques but also propose the potential of RuO2 as a spin source.
PHYSICAL REVIEW LETTERS
(2022)
Article
Materials Science, Multidisciplinary
Guanxiong Qu, Gen Tatara
Summary: In this study, we investigate the intrinsic OHC and SHC in a bismuth semimetal and report a notable difference between their anisotropy. We do not observe a substantial correlation between OHC and SHC, disproving the correlation in a strong SOC regime. We argue that the huge SHC in a Bi semimetal is attributed to its gigantic SOC which strongly affects the hybridization of the p orbitals.
Article
Physics, Applied
Chaoliang Zhang, Yutaro Takeuchi, Shunsuke Fukami, Hideo Ohno
Summary: In this study, we investigate the magnetization switching using a combination of STT and SOT, finding that SOT allows for fast switching of magnetization and STT eliminates the need for an external field. The results show that in the short pulse regime, the Type X structure achieves a switching current one-fourth smaller than the Type Y structure at 200 ps.
APPLIED PHYSICS LETTERS
(2021)
Article
Physics, Applied
Tomohiro Taniguchi
Summary: This study suggests that out-of-plane oscillations can be excited in a ferromagnet with the assistance of field-like torque, providing a new approach for applications such as microwave generators and neuromorphic computing. The research focuses on the dynamic trajectory of magnetization modified by an additional field from the field-like torque, which drives auto-oscillation in a typical nonmagnetic material used in spin Hall devices like tungsten.
APPLIED PHYSICS LETTERS
(2021)
Article
Physics, Multidisciplinary
Cong Xiao, Weikang Wu, Hui Wang, Yue-Xin Huang, Xiaolong Feng, Huiying Liu, Guang-Yu Guo, Qian Niu, Shengyuan A. Yang
Summary: We propose a method for generating spin in second order of electric fields that is time-reversal-even and dominates spin polarization in a wide range of nonmagnetic materials with centrosymmetry. This method also leads to a novel nonlinear spin-orbit torque in magnets. We demonstrate the quantum origin of this effect from the momentum space dipole of the anomalous spin polarizability. First-principles calculations predict sizable spin generation in several nonmagnetic hcp metals, monolayer TiTe2, and ferromagnetic monolayer MnSe2, which can be experimentally detected. Our work opens up new possibilities for nonlinear spintronics in both nonmagnetic and magnetic systems.
PHYSICAL REVIEW LETTERS
(2023)
Article
Chemistry, Multidisciplinary
Hailong Lin, Faguang Yan, Ce Hu, Yuanhui Zheng, Yu Sheng, Wenkai Zhu, Ziao Wang, Houzhi Zheng, Kaiyou Wang
Summary: This study demonstrates the current-assisted magnetization reversal in Fe3GeTe2-based vertical homojunction, which provides support for the potential application of vdW magnetism.
Article
Chemistry, Multidisciplinary
Zhenyi Zheng, Zhizhong Zhang, Xueqiang Feng, Kun Zhang, Yue Zhang, Yu He, Lei Chen, Kelian Lin, Youguang Zhang, Pedram Khalili Amiri, Weisheng Zhao
Summary: In this study, we achieved an anomalous thermal-assisted reduction of spin-orbit torque (SOT) switching current density in a Pt/Co/Tb heterostructure and proposed a multifunctional logic-in-memory device, demonstrating the potential applications and energy efficiency of this mechanism.
Article
Physics, Applied
Tianhui Li, Wei Jia, Tenghua Gao, Satoshi Haku, Zhixiang Ye, Mingxia Qiu, Hongyu An
Summary: This study investigates the generation of spin-orbit torques (SOTs) and the spin Hall effect in oxidized platinum/magnetic oxide heterostructures. The results show that the SOT efficiency drastically decreases with an increase in the oxidation level of Pt(O). Additionally, it is demonstrated that the spin Hall conductivity of Pt is highly sensitive to the electric conductivity.
APPLIED PHYSICS LETTERS
(2022)
Article
Multidisciplinary Sciences
Cuimei Cao, Shiwei Chen, Rui-Chun Xiao, Zengtai Zhu, Guoqiang Yu, Yangping Wang, Xuepeng Qiu, Liang Liu, Tieyang Zhao, Ding-Fu Shao, Yang Xu, Jingsheng Chen, Qingfeng Zhan
Summary: Cubic materials are not expected to exhibit anisotropy in transport phenomena, but we report an anomalous anisotropy of spin current in the (001) film of the noncollinear antiferromagnetic spin source Mn3Pt. This anisotropy originates from the intertwined time reversal-odd and time reversal-even spin Hall effects. By analyzing the symmetry and characterizing the current-induced spin torques in Mn3Pt-based heterostructures, we find that the spin current in Mn3Pt (001) exhibits exotic dependencies on the current direction for all spin components, deviating from that in conventional cubic systems.
NATURE COMMUNICATIONS
(2023)
Article
Multidisciplinary Sciences
G. E. Rowlands, C. A. Ryan, L. Ye, L. Rehm, D. Pinna, A. D. Kent, T. A. Ohki
SCIENTIFIC REPORTS
(2019)
Article
Nanoscience & Nanotechnology
Jakub Zazvorka, Florian Jakobs, Daniel Heinze, Niklas Keil, Sascha Kromin, Samridh Jaiswal, Kai Litzius, Gerhard Jakob, Peter Virnau, Daniele Pinna, Karin Everschor-Sitte, Levente Rozsa, Andreas Donges, Ulrich Nowak, Mathias Klaeui
NATURE NANOTECHNOLOGY
(2019)
Article
Physics, Multidisciplinary
Daniel J. Yates, Alexander G. Abanov, Aditi Mitra
PHYSICAL REVIEW LETTERS
(2020)
Article
Physics, Applied
Pieter Gypens, Bartel Van Waeyenberge, Massimiliano Di Ventra, Jonathan Leliaert, Daniele Pinna
Summary: The end of Moore's law has led to the exploration of low-power computing alternatives, with nanomagnetic logic being a promising approach. However, nanomagnetic logic faces limitations in solving certain problems efficiently. Researchers have introduced nanomagnetic self-organizing logic gates that enable reversible computing, with the ability to solve complex problems like factorization through numerical modeling. This approach opens up new possibilities for exploring memcomputing, a non-traditional computing paradigm.
PHYSICAL REVIEW APPLIED
(2021)
Article
Physics, Multidisciplinary
Daniel J. Yates, Alexander G. Abanov, Aditi Mitra
Summary: This study investigates heating in a Floquet spin chain and demonstrates the existence and stability of long-lived pi edge modes. The lifetime of these modes is determined using exact diagonalization and Krylov techniques. The results show that pi edge modes can remain stable even in the absence of disorder and in the presence of bulk heating.
COMMUNICATIONS PHYSICS
(2022)
Article
Materials Science, Multidisciplinary
Ceren B. Dag, Aditi Mitra
Summary: This paper presents results of Floquet systems in two spatial dimensions, where the Floquet driving breaks the effective time-reversal symmetry. It derives analytical expressions for edge modes, Berry curvature, and orbital magnetization for the induced flat bands. The study also examines the static Haldane model and its flat bands, and shows that Floquet driving of the same model can lead to Chern insulators and anomalous Floquet phases. It finds that the orbital magnetization is enhanced at half filling due to the broken particle-hole symmetry of the Haldane model.
Article
Materials Science, Multidisciplinary
Gabriel E. Topp, Paivi Torma, Dante M. Kennes, Aditi Mitra
Summary: This article derives a general expression for the orbital magnetization of a Floquet system, showing the effects of orbital magnetization under different conditions.
Article
Materials Science, Multidisciplinary
Daniel J. Yates, Aditi Mitra
Summary: This study focuses on the strong zero and pi modes in integrable Floquet spin chains, discussing the effects of weak interactions and presenting manifestations of these modes in different Krylov subspaces. The sensitivity of the Krylov subspace to the branch of the logarithm of the Floquet unitary is highlighted, contrasting it with another subspace obtained from the Arnoldi iteration. The role of interactions and the lifetime of almost strong modes are also discussed in comparison with exact diagonalization.
Article
Materials Science, Multidisciplinary
Muath Natsheh, Andrea Gambassi, Aditi Mitra
Summary: In the periodically driven O(N) model, the critical properties of forming the Floquet time crystal in the prethermal phase are investigated. Key exponents such as v, beta, and theta are determined using a combination of dimensional expansion and exact solutions for large N, showing that these exponents remain the same as those in the absence of drive. The spatial structure of two-point correlation functions near the critical line exhibits longer algebraic decays compared to the absence of a drive, with period doubling and oscillations at a specific wave vector.
Article
Materials Science, Multidisciplinary
Muath Natsheh, Andrea Gambassi, Aditi Mitra
Summary: The periodically driven O(N) model near the critical line exhibits correlation functions with period doubling and power-law decays, compared to the undriven model. The spatiotemporal order of the Floquet time crystal in the driven model leads to more long-ranged position-momentum and momentum-momentum correlations. The light-cone dynamics associated with the driven Floquet time crystal shows a light cone with two distinct velocities scaling as the square-root of the dimensionless drive amplitude.
Article
Physics, Applied
D. Pinna, G. Bourianoff, K. Everschor-Sitte
PHYSICAL REVIEW APPLIED
(2020)
Article
Materials Science, Multidisciplinary
Daniel J. Yates, Alexander G. Abanov, Aditi Mitra
Article
Materials Science, Multidisciplinary
Yonah Lemonik, Aditi Mitra
Article
Materials Science, Multidisciplinary
Daniel J. Yates, Fabian H. L. Essler, Aditi Mitrai
Article
Materials Science, Multidisciplinary
Dillon T. Liu, Javad Shabani, Aditi Mitra
