Статті в журналах: "Ultrafast spintronics"

1

Polley, Debanjan, Akshay Pattabi, Jyotirmoy Chatterjee, Sucheta Mondal, Kaushalya Jhuria, Hanuman Singh, Jon Gorchon, and Jeffrey Bokor. "Progress toward picosecond on-chip magnetic memory." Applied Physics Letters 120, no. 14 (April 4, 2022): 140501. http://dx.doi.org/10.1063/5.0083897.

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We offer a perspective on the prospects of ultrafast spintronics and opto-magnetism as a pathway to high-performance, energy-efficient, and non-volatile embedded memory in digital integrated circuit applications. Conventional spintronic devices, such as spin-transfer-torque magnetic-resistive random-access memory (STT-MRAM) and spin–orbit torque MRAM, are promising due to their non-volatility, energy-efficiency, and high endurance. STT-MRAMs are now entering into the commercial market; however, they are limited in write speed to the nanosecond timescale. Improvement in the write speed of spintronic devices can significantly increase their usefulness as viable alternatives to the existing CMOS-based devices. In this article, we discuss recent studies that advance the field of ultrafast spintronics and opto-magnetism. An optimized ferromagnet–ferrimagnet exchange-coupled magnetic stack, which can serve as the free layer of a magnetic tunnel junction (MTJ), can be optically switched in as fast as ∼3 ps. Integration of ultrafast magnetic switching of a similar stack into an MTJ device has enabled electrical readout of the switched state using a relatively larger tunneling magnetoresistance ratio. Purely electronic ultrafast spin–orbit torque induced switching of a ferromagnet has been demonstrated using ∼6 ps long charge current pulses. We conclude our Perspective by discussing some of the challenges that remain to be addressed to accelerate ultrafast spintronics technologies toward practical implementation in high-performance digital information processing systems.

2

Seifert, Tom S., Liang Cheng, Zhengxing Wei, Tobias Kampfrath, and Jingbo Qi. "Spintronic sources of ultrashort terahertz electromagnetic pulses." Applied Physics Letters 120, no. 18 (May 2, 2022): 180401. http://dx.doi.org/10.1063/5.0080357.

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Spintronic terahertz emitters are broadband and efficient sources of terahertz radiation, which emerged at the intersection of ultrafast spintronics and terahertz photonics. They are based on efficient spin-current generation, spin-to-charge-current conversion, and current-to-field conversion at terahertz rates. In this Editorial, we review the recent developments and applications, the current understanding of the physical processes, and the future challenges and perspectives of broadband spintronic terahertz emitters.

3

El-Ghazaly, Amal, Jon Gorchon, Richard B. Wilson, Akshay Pattabi, and Jeffrey Bokor. "Progress towards ultrafast spintronics applications." Journal of Magnetism and Magnetic Materials 502 (May 2020): 166478. http://dx.doi.org/10.1016/j.jmmm.2020.166478.

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4

Afanasiev, Dmytro, and Alexey V. Kimel. "Ultrafast push for counterintuitive spintronics." Nature Materials 22, no. 6 (June 2023): 673–74. http://dx.doi.org/10.1038/s41563-023-01554-9.

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5

Walowski, Jakob, and Markus Münzenberg. "Perspective: Ultrafast magnetism and THz spintronics." Journal of Applied Physics 120, no. 14 (October 14, 2016): 140901. http://dx.doi.org/10.1063/1.4958846.

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6

Ivanov, B. A. "Spin Dynamics for Antiferromagnets and Ultrafast Spintronics." Journal of Experimental and Theoretical Physics 131, no. 1 (July 2020): 95–112. http://dx.doi.org/10.1134/s1063776120070079.

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7

Zhang, Yue, Xueqiang Feng, Zhenyi Zheng, Zhizhong Zhang, Kelian Lin, Xiaohan Sun, Guanda Wang, et al. "Ferrimagnets for spintronic devices: From materials to applications." Applied Physics Reviews 10, no. 1 (March 2023): 011301. http://dx.doi.org/10.1063/5.0104618.

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Spintronic devices use spin instead of charge to process information and are widely considered as promising candidates for next-generation electronic devices. In past decades, the main motivation in spintronics has been to discover new mechanisms and novel material systems to improve both device performance and the application prospects of spintronics. Recently, researchers have found that ferrimagnetic materials—in which sublattices are coupled antiferromagnetically—offer an emerging platform for realizing high-density, high-speed, and low-power-consumption memory and logic functions. Within such a ferrimagnetic class, vanishing magnetization and ultrafast magnetic dynamics can be achieved by adjusting chemical composition and temperature, among other parameters. Meanwhile, unlike for antiferromagnets, conventional electrical read–write methods remain suitable for ferrimagnets, which is beneficial for applications. In this review, an abundant class of ferrimagnets including oxides and alloys is surveyed, and unique magnetic dynamics and effective methods for manipulating the magnetic states of ferrimagnets are discussed. Finally, novel storage and computing devices based on ferrimagnets are considered, as there are some challenges to be addressed in future applications of ferrimagnets.

8

Matsubara, Masakazu. "Ultrafast Optical Control of Magnetic Interactions in Carrier-Density-Controlled Ferromagnetic Semiconductors." Applied Sciences 9, no. 5 (March 6, 2019): 948. http://dx.doi.org/10.3390/app9050948.

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Investigation of the interaction of ultrashort laser pulses with magnetically ordered materials has become a fascinating research topic in modern magnetism. Especially, the control of magnetic order by sub-ps laser pulses has become a fundamentally important topic with a high potential for future spintronics applications. This paper will review the recent success in optically controlling the magnetic interactions in carrier-density-controlled ferromagnetic semiconductor EuO doped with Gd ions. When the Gd concentration is low, the magnitude of the magnetic interaction is enhanced by the irradiation of ultrashort laser pulses, whereas it is attenuated when the Gd concentration is high. In ferromagnetic Eu1−xGdxO, we thereby demonstrate the strengthening as well as the weakening of the magnetic interaction by 10% and within 3 ps by optically controlling the magnetic exchange interaction. This principle—ultrafast optical control of magnetic interaction—can be applied to future ultrafast opto-spintronics.

9

Telegin, Andrei, and Yurii Sukhorukov. "Magnetic Semiconductors as Materials for Spintronics." Magnetochemistry 8, no. 12 (November 29, 2022): 173. http://dx.doi.org/10.3390/magnetochemistry8120173.

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From the various aspects of spintronics the review highlights the area devoted to the creation of new functional materials based on magnetic semiconductors and demonstrates both the main physical phenomena involved and the technical possibilities of creating various devices: maser, p-n diode with colossal magnetoresistance, spin valve, magnetic lens, optical modulators, spin wave amplifier, etc. Particular attention is paid to promising research directions such as ultrafast spin transport and THz spectroscopy of magnetic semiconductors. Special care has been taken to include a brief theoretical background and experimental results for the new spintronics approach employing magnetostrictive semiconductors—strain-magnetooptics. Finally, it presents top-down approaches for magnetic semiconductors. The mechano-physical methods of obtaining and features of the physical properties of high-density nanoceramics based on complex magnetic oxides are considered. The potential possibility of using these nanoceramics as an absorber of solar energy, as well as in modulators of electromagnetic radiation, is shown.

10

Mashkovich, Evgeny A., Kirill A. Grishunin, Roman M. Dubrovin, Anatoly K. Zvezdin, Roman V. Pisarev, and Alexey V. Kimel. "Terahertz light–driven coupling of antiferromagnetic spins to lattice." Science 374, no. 6575 (December 24, 2021): 1608–11. http://dx.doi.org/10.1126/science.abk1121.

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Coupling up of spins and lattice The development of spintronics and magnetic data storage relies on understanding and controlling the dynamics of magnetic excitations within a material. Of crucial importance for practical applications is how fast the magnetization can be switched. Mashkovich et al . report the use of ultrafast terahertz radiation to create magnon excitations in the antiferromagnet cobalt difluoride that can then be coupled with phonon excitations (see the Perspective by Juraschek and Narang). Using light to control coupling between the spins and the lattice provides a route to manipulate magnetization in antiferromagnetic materials on ultrafast time scales. —ISO

11

Oka, Takashi, and Sota Kitamura. "Floquet Engineering of Quantum Materials." Annual Review of Condensed Matter Physics 10, no. 1 (March 10, 2019): 387–408. http://dx.doi.org/10.1146/annurev-conmatphys-031218-013423.

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Floquet engineering, the control of quantum systems using periodic driving, is an old concept in condensed matter physics dating back to ideas such as the inverse Faraday effect. However, there is a renewed interest in this concept owing to ( a) the rapid developments in laser and ultrafast spectroscopy techniques, ( b) discovery and understanding of various “quantum materials” hosting interesting exotic quantum properties, and ( c) communication with different areas of physics such as artificial matter and nonequilibrium quantum statistical physics. Here, starting from a nontechnical introduction with emphasis on the Floquet picture and effective Hamiltonians, we review the recent applications of Floquet engineering in ultrafast, nonlinear phenomena in the solid state. In particular, Floquet topological states and their application to ultrafast spintronics and strongly correlated electron systems are overviewed.

12

Tengdin, Phoebe, Christian Gentry, Adam Blonsky, Dmitriy Zusin, Michael Gerrity, Lukas Hellbrück, Moritz Hofherr, et al. "Direct light–induced spin transfer between different elements in a spintronic Heusler material via femtosecond laser excitation." Science Advances 6, no. 3 (January 2020): eaaz1100. http://dx.doi.org/10.1126/sciadv.aaz1100.

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Heusler compounds are exciting materials for future spintronics applications because they display a wide range of tunable electronic and magnetic interactions. Here, we use a femtosecond laser to directly transfer spin polarization from one element to another in a half-metallic Heusler material, Co2MnGe. This spin transfer initiates as soon as light is incident on the material, demonstrating spatial transfer of angular momentum between neighboring atomic sites on time scales < 10 fs. Using ultrafast high harmonic pulses to simultaneously and independently probe the magnetic state of two elements during laser excitation, we find that the magnetization of Co is enhanced, while that of Mn rapidly quenches. Density functional theory calculations show that the optical excitation directly transfers spin from one magnetic sublattice to another through preferred spin-polarized excitation pathways. This direct manipulation of spins via light provides a path toward spintronic devices that can operate on few-femtosecond or faster time scales.

13

Patrick, Chris. "Femtosecond spin voltage measurement helps pull spintronics into the ultrafast domain." Scilight 2020, no. 45 (November 6, 2020): 451115. http://dx.doi.org/10.1063/10.0002654.

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14

Chen, Yequan, Zhendong Chen, Wenxuan Sun, Yongda Chen, Xianyang Lu, Xuezhong Ruan, Fengqiu Wang, et al. "Observation of an anisotropic ultrafast spin relaxation process in large-area WTe₂ films." Journal of Applied Physics 131, no. 16 (April 28, 2022): 163903. http://dx.doi.org/10.1063/5.0090935.

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Weyl semimetal Td-WTe2 hosts the natural broken inversion symmetry and strong spin–orbit coupling, which contains profound spin-related physics within a picosecond timescale. However, the comprehensive understanding of ultrafast spin behaviors in WTe2 is lacking due to its limited quality of large-scale films. Here, we report on an anisotropic ultrafast spin dynamics in highly oriented Td-WTe2 films using a femtosecond pump–probe technique at room temperature. A transient spin polarization-flip transition as fast as 0.8 ps is observed upon photoexcitation. The inversed spin is subsequently scattered by defects with a duration of about 5.9 ps. The whole relaxation process exhibits an intriguing dual anisotropy of sixfold and twofold symmetries, which stems from the energy band anisotropy of the WTe2 crystalline structure and the matrix element effect, respectively. Our work enriches the insights into the ultrafast opto-spintronics in topological Weyl semimetals.

15

Zhang, G. P., Y. H. Bai, and Thomas F. George. "Spin Berry points as crucial for ultrafast demagnetization." Modern Physics Letters B 35, no. 13 (March 17, 2021): 2150215. http://dx.doi.org/10.1142/s0217984921502158.

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Laser-induced ultrafast demagnetization has puzzled researchers around the world for over two decades. Intrinsic complexity in electronic, magnetic and phononic subsystems is difficult to understand microscopically. So far, it is not possible to explain demagnetization using a single mechanism, which suggests a crucial piece of information still missing. In this paper, we return to a fundamental aspect of physics: spin and its change within each band in the entire Brillouin zone. We employ face-centered cubic (fcc) Ni as an example and use an extremely dense k mesh to map out spin changes for every band close to the Fermi level along all the high symmetry lines. To our surprise, spin angular momentum at some special k points abruptly changes from [Formula: see text] to [Formula: see text] simply by moving from one crystal momentum point to the next. This explains why intraband transitions, which the spin superdiffusion model is based upon, can induce a sharp spin moment reduction, and why electric current can change spin orientation in spintronics. These special k points, which are called spin Berry points [M. V. Berry, Proc. R. Soc. Lond. A 393 (1984) 45], are not random and appear when several bands are close to each other, so the Berry potential of spin majority states is different from that of spin minority states. Although within a single band, spin Berry points jump, when we group several neighboring bands together, they form distinctive smooth spin Berry lines. It is the band structure that disrupts those lines. Spin Berry points are crucial to laser-induced ultrafast demagnetization and spintronics.

16

Kim, Jonghwan, Xiaoping Hong, Chenhao Jin, Su-Fei Shi, Chih-Yuan S. Chang, Ming-Hui Chiu, Lain-Jong Li, and Feng Wang. "Ultrafast generation of pseudo-magnetic field for valley excitons in WSe2monolayers." Science 346, no. 6214 (December 4, 2014): 1205–8. http://dx.doi.org/10.1126/science.1258122.

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The valley pseudospin is a degree of freedom that emerges in atomically thin two-dimensional transition metal dichalcogenides (MX2). The capability to manipulate it, in analogy to the control of spin in spintronics, can open up exciting opportunities. Here, we demonstrate that an ultrafast and ultrahigh valley pseudo-magnetic field can be generated by using circularly polarized femtosecond pulses to selectively control the valley degree of freedom in monolayer MX2.Using ultrafast pump-probe spectroscopy, we observed a pure and valley-selective optical Stark effect in WSe2monolayers from the nonresonant pump, resulting in an energy splitting of more than 10 milli–electron volts between the K and K′ valley exciton transitions. Our study opens up the possibility to coherently manipulate the valley polarization for quantum information applications.

17

Ito, Keita, Syuta Honda, and Takashi Suemasu. "Transition metal nitrides and their mixed crystals for spintronics." Nanotechnology 33, no. 6 (November 15, 2021): 062001. http://dx.doi.org/10.1088/1361-6528/ac2fe4.

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Abstract Anti-perovskite transition metal nitrides exhibit a variety of magnetic properties—such as ferromagnetic, ferrimagnetic, and paramagnetic—depending on the 3d transition metal. Fe4N and Co4N are ferromagnetic at room temperature (RT), and the minority spins play a dominant role in the electrical transport properties. However, Mn4N is ferrimagnetic at RT and exhibits a perpendicular magnetic anisotropy caused by tensile strain. Around the magnetic compensation in Mn4N induced by impurity doping, researchers have demonstrated ultrafast current-induced domain wall motion reaching 3000 m s−1 at RT, making switching energies lower and switching speed higher compared with Mn4N. In this review article, we start with individual magnetic nitrides—such as Fe4N, Co4N, Ni4N, and Mn4N; describe the nitrides’ features; and then discuss compounds such as Fe4−x A x N (A = Co, Ni, and Mn) and Mn4−x B x N (B = Ni, Co, and Fe) to evaluate nitride properties from the standpoint of spintronics applications. We pay particular attention to preferential sites of A and B atoms in these compounds, based on x-ray absorption spectroscopy and x-ray magnetic circular dichroism.

18

Arslan, M., C. Bese, Z. Tabak, T. Bozdag, E. Duman, and H. G. Yaglioglu. "Experimental observation of transition from type I to type II ultrafast demagnetization dynamics in chemically disordered Fe₆₀Al₄₀ thin film, driven by laser fluence." Journal of Applied Physics 131, no. 9 (March 7, 2022): 093904. http://dx.doi.org/10.1063/5.0073069.

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Understanding of the laser-induced ultrafast demagnetization dynamics is one of the most challenging and hot topics in magnetism research due to its potential applications in magnetic storage devices and the field of spintronics. Recently, a laser-induced switching of ferromagnetism, driven by a disorder–order transition on FeAl thin films, has been experimentally demonstrated. The switching of ferromagnetic ordering by ultrafast laser pulses in FeAl thin films may open new possible applications of this material such as magnetic data storage and manipulation. Since the speed of the magnetic switching of magnetic states in thin films is one of the critical parameters for these applications, here we used time resolved magneto-optical Kerr measurements to investigate the demagnetization dynamics of Fe[Formula: see text]Al[Formula: see text] thin films at room temperature. We have for the first time observed a clear transition from one-step dynamics (type I) to two-step (type II) dynamics in the same material by increasing pump laser fluence. This experimental observation may give a strong confirmation that the ultrafast demagnetization process can be treated as a thermal process and is driven by the difference between temperatures of the electron and spin systems.

19

Agarwal, Rekha, Sandeep Kumar, Niru Chowdhury, Kacho Imtiyaz Ali Khan, Ekta Yadav, Sunil Kumar, and P. K. Muduli. "Strong impact of crystalline twins on the amplitude and azimuthal dependence of THz emission from epitaxial NiO/Pt." Applied Physics Letters 122, no. 8 (February 20, 2023): 082403. http://dx.doi.org/10.1063/5.0138949.

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Ultrafast generation of spin currents involving antiferromagnets is currently attracting tremendous interest. Here, we demonstrate broadband THz emission from a [111]-oriented NiO/Pt bilayer grown on MgO and Al2O3 substrates. The NiO films are grown by pulsed laser deposition, whereas the Pt films are grown by magnetron sputtering. While we obtained epitaxial films on both substrates, NiO films on the Al2O3 substrate showed the presence of crystalline twins. We show that the existence of crystalline twins reduces the THz amplitude by an order of magnitude while simultaneously dramatically changing the azimuthal dependency of the THz amplitude. The findings have significant implications for antiferromagnetic spintronics.

20

Ivanov, B. A. "Ultrafast spin dynamics and spintronics for ferrimagnets close to the spin compensation point (Review)." Low Temperature Physics 45, no. 9 (September 2019): 935–63. http://dx.doi.org/10.1063/1.5121265.

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21

Buryakov, Arseniy, Pavel Avdeev, Dinar Khusyainov, Nikita Bezvikonnyy, Andreas Coclet, Alexey Klimov, Nicolas Tiercelin, Sergey Lavrov, and Vladimir Preobrazhensky. "The Role of Ferromagnetic Layer Thickness and Substrate Material in Spintronic Emitters." Nanomaterials 13, no. 11 (May 23, 2023): 1710. http://dx.doi.org/10.3390/nano13111710.

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In this article, we investigate optically induced terahertz radiation in ferromagnetic FeCo layers of varying thickness on Si and SiO2 substrates. Efforts have been made to account for the influence of the substrate on the parameters of the THz radiation generated by the ferromagnetic FeCo film. The study reveals that the thickness of the ferromagnetic layer and the material of the substrate significantly affect the generation efficiency and spectral characteristics of the THz radiation. Our results also emphasize the importance of accounting for the reflection and transmission coefficients of the THz radiation when analyzing the generation process. The observed radiation features correlate with the magneto-dipole mechanism, triggered by the ultrafast demagnetization of the ferromagnetic material. This research contributes to a better understanding of THz radiation generation mechanisms in ferromagnetic films and may be useful for the further development of THz technology applications in the field of spintronics and other related areas. A key discovery of our study is the identification of a nonmonotonic relationship between the radiation amplitude and pump intensity for thin films on semiconductor substrates. This finding is particularly significant considering that thin films are predominantly used in spintronic emitters due to the characteristic absorption of THz radiation in metals.

22

Chen, Xianzhe, Tomoya Higo, Katsuhiro Tanaka, Takuya Nomoto, Hanshen Tsai, Hiroshi Idzuchi, Masanobu Shiga, et al. "Octupole-driven magnetoresistance in an antiferromagnetic tunnel junction." Nature 613, no. 7944 (January 18, 2023): 490–95. http://dx.doi.org/10.1038/s41586-022-05463-w.

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AbstractThe tunnelling electric current passing through a magnetic tunnel junction (MTJ) is strongly dependent on the relative orientation of magnetizations in ferromagnetic electrodes sandwiching an insulating barrier, rendering efficient readout of spintronics devices1–5. Thus, tunnelling magnetoresistance (TMR) is considered to be proportional to spin polarization at the interface1 and, to date, has been studied primarily in ferromagnets. Here we report observation of TMR in an all-antiferromagnetic tunnel junction consisting of Mn3Sn/MgO/Mn3Sn (ref. 6). We measured a TMR ratio of around 2% at room temperature, which arises between the parallel and antiparallel configurations of the cluster magnetic octupoles in the chiral antiferromagnetic state. Moreover, we carried out measurements using a Fe/MgO/Mn3Sn MTJ and show that the sign and direction of anisotropic longitudinal spin-polarized current in the antiferromagnet7 can be controlled by octupole direction. Strikingly, the TMR ratio (about 2%) of the all-antiferromagnetic MTJ is much larger than that estimated using the observed spin polarization. Theoretically, we found that the chiral antiferromagnetic MTJ may produce a substantially large TMR ratio as a result of the time-reversal, symmetry-breaking polarization characteristic of cluster magnetic octupoles. Our work lays the foundation for the development of ultrafast and efficient spintronic devices using antiferromagnets8–10.

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Rey-de-Castro, R., D. Wang, A. Verevkin, A. Mycielski, and R. Sobolewski. "<tex>$hboxCd_1-xhboxMn_xhboxTe$</tex>Semimagnetic Semiconductors for Ultrafast Spintronics and Magnetooptics." IEEE Transactions On Nanotechnology 4, no. 1 (January 2005): 106–12. http://dx.doi.org/10.1109/tnano.2004.840164.

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Whitaker, Kelly M., Maxim Raskin, Gillian Kiliani, Katja Beha, Stefan T. Ochsenbein, Nils Janssen, Mikhail Fonin, et al. "Spin-on Spintronics: Ultrafast Electron Spin Dynamics in ZnO and Zn1–xCoxO Sol–Gel Films." Nano Letters 11, no. 8 (August 10, 2011): 3355–60. http://dx.doi.org/10.1021/nl201736p.

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25

Bowen, Martin, and Christian Back. "Eric Beaurepaire a pioneer of ultrafast magnetism and organic spintronics passed away on April 24, 2018." Journal of Magnetism and Magnetic Materials 478 (May 2019): 279–80. http://dx.doi.org/10.1016/j.jmmm.2018.11.064.

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26

Luo, Jiaming, Tong Lin, Junjie Zhang, Xiaotong Chen, Elizabeth R. Blackert, Rui Xu, Boris I. Yakobson, and Hanyu Zhu. "Large effective magnetic fields from chiral phonons in rare-earth halides." Science 382, no. 6671 (November 10, 2023): 698–702. http://dx.doi.org/10.1126/science.adi9601.

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Time-reversal symmetry (TRS) is pivotal for materials’ optical, magnetic, topological, and transport properties. Chiral phonons, characterized by atoms rotating unidirectionally around their equilibrium positions, generate dynamic lattice structures that break TRS. Here, we report that coherent chiral phonons, driven by circularly polarized terahertz light pulses, polarize the paramagnetic spins in cerium fluoride in a manner similar to that of a quasi-static magnetic field on the order of 1 tesla. Through time-resolved Faraday rotation and Kerr ellipticity, we found that the transient magnetization is only excited by pulses resonant with phonons, proportional to the angular momentum of the phonons, and growing with magnetic susceptibility at cryogenic temperatures. The observation quantitatively agrees with our spin-phonon coupling model and may enable new routes to investigating ultrafast magnetism, energy-efficient spintronics, and nonequilibrium phases of matter with broken TRS.

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Ogawa, Naoki, Wataru Koshibae, Aron Jonathan Beekman, Naoto Nagaosa, Masashi Kubota, Masashi Kawasaki, and Yoshinori Tokura. "Photodrive of magnetic bubbles via magnetoelastic waves." Proceedings of the National Academy of Sciences 112, no. 29 (July 6, 2015): 8977–81. http://dx.doi.org/10.1073/pnas.1504064112.

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Precise control of magnetic domain walls continues to be a central topic in the field of spintronics to boost infotech, logic, and memory applications. One way is to drive the domain wall by current in metals. In insulators, the incoherent flow of phonons and magnons induced by the temperature gradient can carry the spins, i.e., spin Seebeck effect, but the spatial and time dependence is difficult to control. Here, we report that coherent phonons hybridized with spin waves, magnetoelastic waves, can drive magnetic bubble domains, or curved domain walls, in an iron garnet, which are excited by ultrafast laser pulses at a nonabsorbing photon energy. These magnetoelastic waves were imaged by time-resolved Faraday microscopy, and the resultant spin transfer force was evaluated to be larger for domain walls with steeper curvature. This will pave a path for the rapid spatiotemporal control of magnetic textures in insulating magnets.

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Zhang, Guangfu, Ye Tian, Yangbao Deng, Dongchu Jiang, and Shuguang Deng. "Spin-Wave-Driven Skyrmion Motion in Magnetic Nanostrip." Journal of Nanotechnology 2018 (2018): 1–5. http://dx.doi.org/10.1155/2018/2602913.

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The photon-assisted magnetic recording utilizes the ultrafast laser to excite the spin wave in the magnetic nanostructures and accordingly switch its magnetization state. Here, by means of micromagnetic simulation, the motion of magnetic skyrmions, a topologically protected chiral magnet with few nanometer size, induced by the spin wave is studied. It is found that the magnetic skyrmion can move in the same direction of spin-wave propagation, which is first accelerated and then decelerated exponentially. The magnetic skyrmion motion originated from the robust coupling of the spin waves with the skyrmion, through the SW’s linear momentum transfer torque acting on the skyrmion. Besides amplitude, the reflectivity of the spin wave by skyrmion has tremendous impact on the velocity of skyrmion motion. The skyrmion velocities are mainly determined by the reflectivity, when the spin-wave amplitude is almost identical. Our results give guidance for the design and development of spin-wave control spintronics.

29

Nan, Tianxiang, Yeonbae Lee, Shihao Zhuang, Zhongqiang Hu, James D. Clarkson, Xinjun Wang, Changhyun Ko, et al. "Electric-field control of spin dynamics during magnetic phase transitions." Science Advances 6, no. 40 (October 2020): eabd2613. http://dx.doi.org/10.1126/sciadv.abd2613.

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Controlling magnetization dynamics is imperative for developing ultrafast spintronics and tunable microwave devices. However, the previous research has demonstrated limited electric-field modulation of the effective magnetic damping, a parameter that governs the magnetization dynamics. Here, we propose an approach to manipulate the damping by using the large damping enhancement induced by the two-magnon scattering and a nonlocal spin relaxation process in which spin currents are resonantly transported from antiferromagnetic domains to ferromagnetic matrix in a mixed-phased metallic alloy FeRh. This damping enhancement in FeRh is sensitive to its fraction of antiferromagnetic and ferromagnetic phases, which can be dynamically tuned by electric fields through a strain-mediated magnetoelectric coupling. In a heterostructure of FeRh and piezoelectric PMN-PT, we demonstrated a more than 120% modulation of the effective damping by electric fields during the antiferromagnetic-to-ferromagnetic phase transition. Our results demonstrate an efficient approach to controlling the magnetization dynamics, thus enabling low-power tunable electronics.

30

Jenkins, Adam J., Ziliang Mao, Aiko Kurimoto, L. Tyler Mix, Natia Frank, and Delmar S. Larsen. "Ultrafast Spintronics: Dynamics of the Photoisomerization-Induced Spin–Charge Excited-State (PISCES) Mechanism in Spirooxazine-Based Photomagnetic Materials." Journal of Physical Chemistry Letters 9, no. 18 (August 29, 2018): 5351–57. http://dx.doi.org/10.1021/acs.jpclett.8b02166.

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Jakobs, F., and U. Atxitia. "Atomistic spin model of single pulse toggle switching in Mn₂Ru_xGa Heusler alloys." Applied Physics Letters 120, no. 17 (April 25, 2022): 172401. http://dx.doi.org/10.1063/5.0084846.

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Single femtosecond-pulse toggle switching of ferrimagnetic alloys is an essential building block for ultrafast spintronics. It is believed that for switching to occur in these ferrimagnets, the individual sublattices must have very different (element-specific) demagnetization dynamics. This suggests that ferrimagnets composed of two different elements, such as rare-earth transition-metal alloys, are necessary for switching. However, experimental observations of toggle switching in the Heusler alloy Mn2Ru xGa, which has two crystallographically nonequivalent Mn sublattices with antiparallel aligned moments, have questioned these assertions. To shed some light on this question, we present an atomistic spin model for the simulation of single pulse toggle switching of Mn2Ru xGa. The magnetic parameters entering our model are extracted from previous experimental observations. We show that our model is able to quantitatively reproduce the experimentally measured magnetization dynamics of single pulse toggle switching. We demonstrate that toggle switching in Mn2Ru xGa is possible even when both Mn sublattices demagnetize at very similar rates, in contradiction to the previous hypothesis about the importance of element-specific demagnetization rates in this process.

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Jiang, Caijian, Donglin Liu, Xinyu Song, Yifeng Wu, Hai Li, and Chudong Xu. "Single-shot all-optical switching of magnetization in TbFe." Journal of Physics D: Applied Physics 57, no. 19 (February 15, 2024): 195001. http://dx.doi.org/10.1088/1361-6463/ad26ef.

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Abstract Thermally induced magnetization switching (TIMS) relying solely on a single laser without any applied magnetic field is a key research direction of current spintronics. Most studies on TbFe so far have focused on helicity-dependent all-optical switching (HD-AOS). In this work, we observe the TIMS on TbFe alloys excited by atomic spin dynamics simulations combined with a two-temperature model. The results show that the magnetization switching of TbFe can be found under certain damping conditions. In addition, we further investigated the reasons why energy density leads to the opposite switching time behavior of Tb and Fe, and our research results also found that changes in damping can affect the concentration and energy density range of the switching, as well as the maximum pulse duration. The dynamic behavior indicates that TbFe switching in 2 ps or less. Our findings widen the basis for fast optical switching of magnetization and break new ground for engineered materials that can be used for nonvolatile ultrafast switching using ultrashort pulses of light.

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Petrov, Andrey V., Sergey I. Nikitin, Lenar R. Tagirov, Amir I. Gumarov, Igor V. Yanilkin, and Roman V. Yusupov. "Ultrafast signatures of magnetic inhomogeneity in Pd₁₋_xFe_x (x ≤ 0.08) epitaxial thin films." Beilstein Journal of Nanotechnology 13 (August 25, 2022): 836–44. http://dx.doi.org/10.3762/bjnano.13.74.

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A series of Pd1−xFex alloy epitaxial films (x = 0, 0.038, 0.062, and 0.080), a material promising for superconducting spintronics, was prepared and studied with ultrafast optical and magneto-optical laser spectroscopy in a wide temperature range of 4–300 K. It was found that the transition to the ferromagnetic state causes a qualitative change of both the reflectivity and the magneto-optical Kerr effect transients. A nanoscale magnetic inhomogeneity of the ferromagnet/paramagnet type inherent in the palladium-rich Pd1−xFex alloys reveals itself through the occurrence of a relatively slow, 10–25 ps, photoinduced demagnetization component following a subpicosecond one; the former vanishes at low temperatures only in the x = 0.080 sample. We argue that the 10 ps timescale demagnetization originates most probably from the diffusive transport of d electrons under the condition of nanoscale magnetic inhomogeneities. The low-temperature fraction of the residual paramagnetic phase can be deduced from the magnitude of the slow reflectivity relaxation component. It is estimated as ≈30% for x = 0.038 and ≈15% for x = 0.062 films. The minimal iron content ensuring the magnetic homogeneity of the ferromagnetic state in the Pd1−xFex alloy at low temperatures is about 7–8 atom %.

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Deng, Liangzi, Hung-Cheng Wu, Alexander P. Litvinchuk, Noah F. Q. Yuan, Jey-Jau Lee, Rabin Dahal, Helmuth Berger, Hung-Duen Yang, and Ching-Wu Chu. "Room-temperature skyrmion phase in bulk Cu2OSeO3 under high pressures." Proceedings of the National Academy of Sciences 117, no. 16 (April 2, 2020): 8783–87. http://dx.doi.org/10.1073/pnas.1922108117.

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A skyrmion state in a noncentrosymmetric helimagnet displays topologically protected spin textures with profound technological implications for high-density information storage, ultrafast spintronics, and effective microwave devices. Usually, its equilibrium state in a bulk helimagnet occurs only over a very restricted magnetic field–temperature phase space and often in the low-temperature region near the magnetic transition temperature Tc. We have expanded and enhanced the skyrmion phase region from the small range of 55 to 58.5 K to 5 to 300 K in single-crystalline Cu2OSeO3 by pressures up to 42.1 GPa through a series of phase transitions from the cubic P213, through orthorhombic P212121 and monoclinic P21, and finally to the triclinic P1 phase, using our newly developed ultrasensitive high-pressure magnetization technique. The results are in agreement with our Ginzburg–Landau free energy analyses, showing that pressures tend to stabilize the skyrmion states and at higher temperatures. The observations also indicate that the skyrmion state can be achieved at higher temperatures in various crystal symmetries, suggesting the insensitivity of skyrmions to the underlying crystal lattices and thus the possible more ubiquitous presence of skyrmions in helimagnets.

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Zhang, G. P., M. Murakami, M. S. Si, Y. H. Bai, and Thomas F. George. "Understanding all-optical spin switching: Comparison between experiment and theory." Modern Physics Letters B 32, no. 28 (October 4, 2018): 1830003. http://dx.doi.org/10.1142/s021798491830003x.

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Information technology depends on how one can control and manipulate signals accurately and quickly. Transistors are at the core of modern technology and are based on electron charges. But as the device dimension shrinks, heating becomes a major problem. The spintronics explores the spin degree of electrons and thus bypasses the heat, at least in principle. For this reason, spin-based technology offers a possible solution. In this review, we survey some of the latest developments in all-optical switching (AOS), where ultrafast laser pulses are able to reverse spins from one direction to the other deterministically. But AOS only occurs in a special group of magnetic samples and within a narrow window of laser parameters. Some samples need multiple pulses to switch spins, while others need a single-shot pulse. To this end, there are several models available, but the underlying mechanism is still under debate. This review is different from other prior reviews in two aspects. First, we sacrifice the completeness of reviewing existing studies, while focusing on a limited set of experimental results that are highly reproducible in different labs and provide actual switched magnetic domain images. Second, we extract the common features from existing experiments that are critical to AOS, without favoring a particular switching mechanism. We emphasize that given the limited experimental data, it is really premature to identify a unified mechanism. We compare these features with our own model prediction, without resorting to a phenomenological scheme. We hope that this review serves the broad readership well.

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Kumar, Sandeep, and Sunil Kumar. "Ultrafast light-induced THz switching in exchange-biased Fe/Pt spintronic heterostructure." Applied Physics Letters 120, no. 20 (May 16, 2022): 202403. http://dx.doi.org/10.1063/5.0091934.

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The ultrafast optical control of magnetization in spintronic structures enables one to access to the high-speed information processing, approaching the realm of terahertz (THz). Femtosecond visible/near-infrared laser-driven ferromagnetic/nonmagnetic metallic spintronic heterostructures-based THz emitters combine the aspects from the ultrafast photo-induced dynamics and spin-charge inter-conversion mechanisms through the generation of THz electromagnetic pulses. In this Letter, we demonstrate photoexcitation density-dependent induced exchange-bias tunability and THz switching in an annealed Fe/Pt thin-film heterostructure, which otherwise is a widely used conventional spintronic THz emitter. By combining the exchange-bias effect along with THz emission, the photo-induced THz switching is observed without any applied magnetic field. These results pave the way for an all-optical ultrafast mechanism to exchange-bias tuning in spintronic devices for high-density storage, read/write magnetic memory applications.

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Agarwal, Piyush, Yingshu Yang, James Lourembam, Rohit Medwal, Marco Battiato, and Ranjan Singh. "Terahertz spintronic magnetometer (TSM)." Applied Physics Letters 120, no. 16 (April 18, 2022): 161104. http://dx.doi.org/10.1063/5.0079989.

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A ferromagnetic metal consists of localized electrons and conduction electrons coupled through strong exchange interaction. Together, these localized electrons contribute to the magnetization of the system, while conduction electrons lead to the formation of spin and charge current. Femtosecond out of equilibrium photoexcitation of ferromagnetic thin films generates a transient spin current at ultrafast timescales that have opened a route to probe magnetism offered by the conduction electrons. In the presence of a neighboring heavy metal layer, the non-equilibrium spin current is converted into a pulsed charge current and gives rise to terahertz (THz) emission. Here, we propose and demonstrate a tool known as the terahertz spintronic magnetometry. The hysteresis loop obtained by sweeping terahertz (THz) pulse amplitude as a function of the magnetic field is in excellent agreement with the vibrating-sample magnetometer measurements. Furthermore, a modified transfer-matrix method employed to model the THz propagation within the heterostructure theoretically elucidates a linear relationship between the THz pulse amplitude and sample magnetization. The strong correlation, thus, reveals spintronic terahertz emission as an ultrafast magnetometry tool with reliable in-plane magnetization detection, highlighting its technological importance in the characterization of ferromagnetic thin-films through terahertz spintronic emission spectroscopy.

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Keatley, P. S., V. V. Kruglyak, P. Gangmei, and R. J. Hicken. "Ultrafast magnetization dynamics of spintronic nanostructures." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 369, no. 1948 (August 13, 2011): 3115–35. http://dx.doi.org/10.1098/rsta.2010.0324.

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The ultrafast (sub-nanosecond) magnetization dynamics of ferromagnetic thin films and elements that find application in spintronic devices is reviewed. The major advances in the understanding of magnetization dynamics in the two decades since the discovery of giant magnetoresistance and the prediction of spin-transfer torque are discussed, along with the plethora of new experimental techniques developed to make measurements on shorter length and time scales. Particular consideration is given to time-resolved measurements of the magneto-optical Kerr effect, and it is shown how a succession of studies performed with this technique has led to an improved understanding of the dynamics of nanoscale magnets. The dynamics can be surprisingly rich and complicated, with the latest studies of individual nanoscale elements showing that the dependence of the resonant mode spectrum upon the physical structure is still not well understood. Finally, the article surveys the prospects for development of high-frequency spintronic devices and highlights areas in which further study of fundamental properties will be required within the coming decade.

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Wang Jiaqi, 王家琦, 代明聪 Dai Mingcong, 马一航 Ma Yihang, 王有为 Wang Youwei, 张子建 Zhang Zijian, 才家华 Cai Jiahua, 陈鹏 Chen Peng, 万蔡华 Wan Caihua, 韩秀峰 Han Xiufeng та 吴晓君 Wu Xiaojun. "基于超快太赫兹散射型扫描近场光学显微镜的自旋电子太赫兹发射光谱技术（特邀）". Laser & Optoelectronics Progress 61, № 3 (2024): 0325001. http://dx.doi.org/10.3788/lop232441.

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40

Papaioannou, Evangelos Th, and René Beigang. "THz spintronic emitters: a review on achievements and future challenges." Nanophotonics, December 18, 2020. http://dx.doi.org/10.1515/nanoph-2020-0563.

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AbstractThe field of THz spintronics is a novel direction in the research field of nanomagnetism and spintronics that combines magnetism with optical physics and ultrafast photonics. The experimental scheme of the field involves the use of femtosecond laser pulses to trigger ultrafast spin and charge dynamics in thin films composed of ferromagnetic and nonmagnetic thin layers, where the nonmagnetic layer features a strong spin–orbit coupling. The technological and scientific key challenges of THz spintronic emitters are to increase their intensity and to shape the frequency bandwidth. To achieve the control of the source of the radiation, namely the transport of the ultrafast spin current is required. In this review, we address the generation, detection, efficiency and the future perspectives of THz emitters. We present the state-of-the-art of efficient emission in terms of materials, geometrical stack, interface quality and patterning. The impressive so far results hold the promise for new generation of THz physics based on spintronic emitters.

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Kampfrath, Tobias, Andrei Kirilyuk, Stéphane Mangin, Sangeeta Sharma, and Martin Weinelt. "Ultrafast and terahertz spintronics: Guest editorial." Applied Physics Letters 123, no. 5 (July 31, 2023). http://dx.doi.org/10.1063/5.0167151.

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Spin-based electronics (spintronics) aims at extending electronic functionalities, which rely on the electron charge as information carrier, by the spin of the electron. To make spintronics competitive and compatible with other information carriers like photons and electrons, their speed needs to be pushed to femtosecond time scales and, thus, terahertz frequencies. In ultrafast and terahertz spintronics, femtosecond optical and terahertz electromagnetic pulses are used to induce spin torque and spin transport and to monitor the subsequent time evolution. The two approaches, sometimes referred to as femto-magnetism and terahertz magnetism, have provided new, surprising, and relevant insight as well as applications for spintronics. Examples include the ultrafast optical switching of magnetic order and the generation of broadband terahertz electromagnetic fields. This APL Special Topic Collection is dedicated to provide a platform for the newest developments and future trends in the very active, dynamic, and exciting research field of ultrafast and terahertz spintronics.

42

Tzschaschel, Christian, Takuya Satoh, and Manfred Fiebig. "Efficient spin excitation via ultrafast damping-like torques in antiferromagnets." Nature Communications 11, no. 1 (December 2020). http://dx.doi.org/10.1038/s41467-020-19749-y.

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AbstractDamping effects form the core of many emerging concepts for high-speed spintronic applications. Important characteristics such as device switching times and magnetic domain-wall velocities depend critically on the damping rate. While the implications of spin damping for relaxation processes are intensively studied, damping effects during impulsive spin excitations are assumed to be negligible because of the shortness of the excitation process. Herein we show that, unlike in ferromagnets, ultrafast damping plays a crucial role in antiferromagnets because of their strongly elliptical spin precession. In time-resolved measurements, we find that ultrafast damping results in an immediate spin canting along the short precession axis. The interplay between antiferromagnetic exchange and magnetic anisotropy amplifies this canting by several orders of magnitude towards large-amplitude modulations of the antiferromagnetic order parameter. This leverage effect discloses a highly efficient route towards the ultrafast manipulation of magnetism in antiferromagnetic spintronics.

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Joy, Ajin, Sreyas Satheesh, and P. S. Anil Kumar. "Extremely energy-efficient, magnetic field-free, skyrmion-based memristors for neuromorphic computing." Applied Physics Letters 123, no. 21 (November 20, 2023). http://dx.doi.org/10.1063/5.0177232.

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The human brain can process information more efficiently than computers due to the dynamics of neurons and synapses. Mimicking such a system can lead to the practical implementation of artificial spiking neural networks. Spintronic devices have been shown to be an ideal solution for realizing the hardware required for neuromorphic computing. Skyrmions prove to be an effective candidate as information carriers owing to their topological protection and particle-like nature. Ferrimagnet and antiferromagnet-based spintronics have been employed previously to obtain an ultrafast simulation of artificial synapses and neurons. Here, we have proposed a ferromagnetic device of stack Ta3nmPt3nmCu0.65nmCo0.5nmPt1nm that is capable of ultrafast simulation of artificial neurons and synapses, owing to the high velocity of the stabilized skyrmions in the system. Electrical pulses of nanosecond pulse width were used to control the accumulation and dissipation of skyrmions in the system, analogous to the variations in the synaptic weights. Lateral structure inversion asymmetry is used to bring about a field-free switching in the system, leading to an energy-efficient switching process. Magnetic field-free deterministic switching and low pulse width current pulses drastically reduce energy consumption by 106 times compared to the existing ferromagnet-based neuromorphic devices. Artificial neuron, synapse, and memristor functionalities have been reproduced on the same device with characteristic time scales and field-free switching, better than any existing ferromagnet-based neuromorphic devices. The results recognize ferromagnet-based skyrmions as viable candidates for ultrafast neuromorphic spintronics capable of executing cognitive tasks with extremely high efficiency.

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Wang, Luding, Houyi Cheng, Pingzhi Li, Youri L. W. van Hees, Yang Liu, Kaihua Cao, Reinoud Lavrijsen, Xiaoyang Lin, Bert Koopmans, and Weisheng Zhao. "Picosecond optospintronic tunnel junctions." Proceedings of the National Academy of Sciences 119, no. 24 (June 6, 2022). http://dx.doi.org/10.1073/pnas.2204732119.

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Significance Spintronic devices have become promising candidates for next-generation memory architecture. However, state-of-the-art devices, such as perpendicular magnetic tunnel junctions (MTJs), are still fundamentally constrained by a subnanosecond speed limitation, which has remained a long-lasting scientific obstacle in the ultrafast spintronics field. The highlight of our work is the demonstration of an optospintronic tunnel junction, an all-optical MTJ device which emerges as a new category of integrated photonic–spintronic memory. We demonstrate 1) laser-induced deterministic and efficient writing by an all-optical approach and electrical readout by tunnel magnetoresistance, 2) writing speed within 10 ps, demonstrated by femtosecond-resolved measurements, and 3) integration with state-of-the-art MTJ performance and a complementary metal–oxide–semiconductor-compatible fabrication progress.

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Ghasemzadeh, Farzaneh, mohsen farokhnezhad та Mahdi Esmaeilzadeh. "Ultrafast switching in spin ﬁeld-eﬀect transistors based on borophene nanoribbons". Physical Chemistry Chemical Physics, 2024. http://dx.doi.org/10.1039/d4cp00239c.

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Borophene, owing to the high mobility and long spin coherent length of its carriers, presents signiﬁcant opportunities in ultrafast spintronics. In this research, we investigate the spin-dependent conductance of a...

46

Walowski, Jakob, and Markus Muenzenberg. "ChemInform Abstract: Perspective: Ultrafast Magnetism and THz Spintronics." ChemInform 47, no. 48 (November 2016). http://dx.doi.org/10.1002/chin.201648262.

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47

Remy, Quentin, Julius Hohlfeld, Maxime Vergès, Yann Le Guen, Jon Gorchon, Grégory Malinowski, Stéphane Mangin, and Michel Hehn. "Accelerating ultrafast magnetization reversal by non-local spin transfer." Nature Communications 14, no. 1 (January 27, 2023). http://dx.doi.org/10.1038/s41467-023-36164-1.

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AbstractWhen exciting a magnetic material with a femtosecond laser pulse, the amplitude of magnetization is no longer constant and can decrease within a time scale comparable to the duration of the optical excitation. This ultrafast demagnetization can even trigger an ultrafast, out of equilibrium, phase transition to a paramagnetic state. The reciprocal effect, namely an ultrafast remagnetization from the zero magnetization state, is a necessary ingredient to achieve a complete ultrafast reversal. However, the speed of remagnetization is limited by the universal critical slowing down which appears close to a phase transition. Here we demonstrate that magnetization can be reversed in a few hundreds of femtoseconds by overcoming the critical slowing down thanks to ultrafast spin cooling and spin heating mechanisms. We foresee that these results outline the potential of ultrafast spintronics for future ultrafast and energy efficient magnetic memory and storage devices. Furthermore, this should motivate further theoretical works in the field of femtosecond magnetization reversal.

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Qin, Peixin, Xiaorong Zhou, Li Liu, Ziang Meng, Han Yan, Hongyu Chen, Xiaoning Wang, Xiaojun Wu, and Zhiqi Liu. "Antiferromagnetic spintronics: towards high-density and ultrafast information technology." Science Bulletin, April 2023. http://dx.doi.org/10.1016/j.scib.2023.04.024.

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Matsubara, Masakazu, Takatsugu Kobayashi, Hikaru Watanabe, Youichi Yanase, Satoshi Iwata, and Takeshi Kato. "Polarization-controlled tunable directional spin-driven photocurrents in a magnetic metamaterial with threefold rotational symmetry." Nature Communications 13, no. 1 (November 7, 2022). http://dx.doi.org/10.1038/s41467-022-34374-7.

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AbstractFuture spintronics and quantum technologies will require a portfolio of techniques for manipulating electron spins in functional nanodevices. Especially, the establishment of the methods to control spin current is the key ingredient essential for the transfer and processing of information, enabling faster and low-energy operation. However, a universal method for manipulating spin currents with full-directional controllability and tunable magnitude has not been established. Here we show that an artificial material called a magnetic metamaterial (MM), which possesses a novel spintronic functionality not exhibited by the original substance, generates photo-driven ultrafast spin currents at room temperature via the magneto-photogalvanic effect. By tuning the polarization state of the excitation light, these spin currents can be directed with tunable magnitude along an arbitrary direction in the two-dimensional plane of the MM. This new concept may guide the design and creation of artificially engineered opto-spintronic functionalities beyond the limitations of conventional material science.

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Xu, Shuai, Hao Xie, Yiming Zhang, Chenrong Zhang, Wei Jin, Georgios Lefkidis, Wolfgang Hübner та Chun Li. "Designing spintronic devices in two-dimensional γ-graphyne: from ultrafast spin dynamics to logic applications". Journal of Physics D: Applied Physics, 5 квітня 2024. http://dx.doi.org/10.1088/1361-6463/ad3b09.

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Abstract The integration of two-dimensional (2D) materials into spintronics represents a frontier in the development of novel computational devices. In this work, by utilizing ab initio many-body theory, we investigate the spin dynamics within the Co-doped γ-graphyne structure, with a particular emphasis on the role of cobalt atoms as magnetic centers. The result reveals that each cobalt atom on the γ-graphyne hosts states with enough spin-density localization to facilitate both local spin flips and global spin transfers. The spin-dynamic processes in our study are characterized by ultrafast time scales and high fidelities, demonstrating efficient spin control in the system. Building upon these spin dynamics processes, we theoretically construct a spin-based Reset-Set (RS) latch, thus demonstrating the feasibility of sophisticated logic operations in our system. Such spin-based devices exhibit the advantages of nano-spintronics over conventional-electronic approaches, offering lower energy consumption, faster operational speeds, and greater potential for miniaturization. The results highlight the efficacy of γ-graphyne nanoflakes doped with cobalt atoms as spin-information processing units, signifying a pivotal advancement in the incorporation of graphyne-based materials into sophisticated spintronic devices. This research paves the way for their application in areas such as data storage, quantum computing, and the development of complex logic-processing architectures.

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