Article
Chemistry, Multidisciplinary
Bin He, Riccardo Tomasello, Xuming Luo, Ran Zhang, Zhuyang Nie, Mario Carpentieri, Xiufeng Han, Giovanni Finocchio, Guoqiang Yu
Summary: This study demonstrates the realization of a 9-bit skyrmion racetrack memory with all-electrical controllable functionalities in the same device. By generating a tailored nonuniform distribution of magnetic anisotropy through laser irradiation, robust control of skyrmion nucleation and position as well as effective electrical detection of skyrmions are achieved.
Article
Chemistry, Multidisciplinary
Pablo Olleros-Rodriguez, Mara Strungaru, Sergiu Ruta, Paul-Iulian Gavriloaea, Adrian Gudin, Paolo Perna, Roy Chantrell, Oksana Chubykalo-Fesenko
Summary: By using femtosecond laser heating, we demonstrate the possibility of creating metastable skyrmion lattices in cobalt-based trilayers. The fast relaxation of magnon drops generated by high temperature ultrafast excitation leads to the acquisition and quenching of the skyrmion topological protection. These results provide insight into the dynamics of highly non-equilibrium spin excitations and open up additional pathways for skyrmion-based information technologies.
Article
Multidisciplinary Sciences
Mateusz Zelent, Mathieu Moalic, Michal Mruczkiewicz, Xiaoguang Li, Yan Zhou, Maciej Krawczyk
Summary: Magnetic skyrmions, small stable magnetic structures with intriguing properties, can be used for data storage applications. Hybrid nanostructures composed of skyrmions and soft magnetic material have advantages for developing spintronic and magnonic devices. The mutual coupling between magnetization textures can be explored by confining a Neel-type skyrmion within a nanodot placed on top of a ferromagnetic in-plane magnetized stripe.
SCIENTIFIC REPORTS
(2023)
Article
Chemistry, Multidisciplinary
Lisa-Marie Kern, Bastian Pfau, Victor Deinhart, Michael Schneider, Christopher Klose, Kathinka Gerlinger, Steffen Wittrock, Dieter Engel, Ingo Will, Christian M. Guenther, Rein Liefferink, Johan H. Mentink, Sebastian Wintz, Markus Weigand, Meng-Jie Huang, Riccardo Battistelli, Daniel Metternich, Felix Buettner, Katja Hoeflich, Stefan Eisebitt
Summary: This study demonstrates the precise control of skyrmion nucleation by nanopatterning the material with an ion beam, enabling future studies and applications of skyrmion dynamics.
Article
Physics, Applied
Kathinka Gerlinger, Bastian Pfau, Felix Buettner, Michael Schneider, Lisa-Marie Kern, Josefin Fuchs, Dieter Engel, Christian M. Guenther, Mantao Huang, Ivan Lemesh, Lucas Caretta, Alexandra Churikova, Piet Hessing, Christopher Klose, Christian Strueber, Clemens von Korff Schmising, Siying Huang, Angela Wittmann, Kai Litzius, Daniel Metternich, Riccardo Battistelli, Kai Bagschik, Alexandr Sadovnikov, Geoffrey S. D. Beach, Stefan Eisebitt
Summary: Magnetic skyrmions can be created and annihilated in ferromagnetic multilayers using single femtosecond infrared laser pulses above a material-dependent fluence threshold. The number of skyrmions created can be directly and robustly controlled via the applied field and the laser fluence. Proposed applications include all-optical writing and deletion, an ultrafast skyrmion reshuffling device for probabilistic computing, and a combined optical and spin-orbit torque-controlled racetrack.
APPLIED PHYSICS LETTERS
(2021)
Article
Physics, Applied
Md Golam Morshed, Hamed Vakili, Avik W. Ghosh
Summary: Magnetic skyrmions are promising for low-power high-density memory and logic applications due to their attractive features. By varying material parameters and notch geometries, researchers have identified optimal energy barriers for stabilizing skyrmions, potentially providing years of positional stability for long-term memory applications. This study opens up possibilities for designing practical skyrmion-based racetrack geometries for spintronics applications.
PHYSICAL REVIEW APPLIED
(2022)
Article
Multidisciplinary Sciences
Romeo Juge, Naveen Sisodia, Joseba Urrestarazu Larranaga, Qiang Zhang, Van Tuong Pham, Kumari Gaurav Rana, Brice Sarpi, Nicolas Mille, Stefan Stanescu, Rachid Belkhou, Mohamad-Assaad Mawass, Nina Novakovic-Marinkovic, Florian Kronast, Markus Weigand, Joachim Graefe, Sebastian Wintz, Simone Finizio, Joerg Raabe, Lucia Aballe, Michael Foerster, Mohamed Belmeguenai, Liliana D. Buda-Prejbeanu, Johan Pelloux-Prayer, Justin M. Shaw, Hans T. Nembach, Laurent Ranno, Gilles Gaudin, Olivier Boulle
Summary: This study successfully observed isolated skyrmions in synthetic antiferromagnets and confirmed their properties and control mechanisms through micromagnetic simulations and an analytical model. Furthermore, the study demonstrated the formation of synthetic antiferromagnetic skyrmions using current and light.
NATURE COMMUNICATIONS
(2022)
Article
Chemistry, Multidisciplinary
Valentin Ahrens, Clara Kiesselbach, Luca Gnoli, Domenico Giuliano, Simon Mendisch, Martina Kiechle, Fabrizio Riente, Markus Becherer
Summary: This study demonstrates the easy access to the skyrmion phase in W/CoFeB/MgO thin films by using optimized focused ion beam irradiation and annealing protocols. By analyzing ion-beam-engineered skyrmion hosting wires excited by sub-100 ns current pulses, the possibilities of controlling skyrmion nucleation, guiding their motion, and controlling their annihilation are explored. Overall, the key elements needed to develop extensive skyrmion networks are presented.
ADVANCED MATERIALS
(2023)
Article
Physics, Applied
Yunxi Jiang, Hao Yu, Xi Chen
Summary: Magnetic skyrmions are particle-like topological protected spin structures that can be driven by electric current. We demonstrate a single skyrmion-based multilevel data storage device that could also work as the potential artificial synapse for neuromorphic computing. Our work shows that the anisotropic magnetoresistance (AMR) induced by the skyrmion can help detect a single skyrmion without the magnetic tunnel junction. Additionally, the skyrmion manipulated by pinning provides an approach for precise control and helps realize skyrmion-based in-memory computing.
JOURNAL OF APPLIED PHYSICS
(2023)
Article
Materials Science, Multidisciplinary
R. C. Silva, R. L. Silva, V. L. Carvalho-Santos, W. A. Moura-Melo, A. R. Pereira
Summary: In this study, we investigate the dynamics of two skyrmions in an antiferromagnetic bilayer system. We find that the skyrmions can form a bound state through ferromagnetic exchange coupling and analyze how their dynamics are influenced by the application of an electric current. We also examine the conditions for the nucleation of the bound state and analyze its robustness under different circumstances.
JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS
(2022)
Article
Physics, Multidisciplinary
Sumit Ghosh, Frank Freimuth, Olena Gomonay, Stefan Bluegel, Yuriy Mokrousov
Summary: The authors investigate the theoretical physics of laser-driven chiral magnetism, highlighting the connection between the quantum evolution of electronic states and the classical spin dynamics. They find that laser-driven chirality can exist and be stable on the nanosecond timescale without the need for external fields or intrinsic spin-orbit interaction.
COMMUNICATIONS PHYSICS
(2022)
Article
Physics, Condensed Matter
R. C. Silva, R. L. Silva, A. R. Pereira
Summary: This paper investigates a magnetic racetrack system composed of three materials with different properties. Skyrmions and antiskyrmions are created in their respective sectors and impelled to the interface by applying a spin-polarized current, forming a skyrmion-antiskyrmion pair. The engineered racetrack can support a sequence of several skyrmion-antiskyrmion pair structures in motion, forming a current.
JOURNAL OF PHYSICS-CONDENSED MATTER
(2021)
Article
Chemistry, Multidisciplinary
Cristina Balan, Johannes W. van de Jagt, Aymen Fassatoui, Jose Pena Garcia, Vincent Jeudy, Andre Thiaville, Marlio Bonfim, Jan Vogel, Laurent Ranno, Dafine Ravelosona, Stefania Pizzini
Summary: This research illustrates the effect of He+ irradiation on the magnetization reversal and domain wall dynamics of Pt/Co/AlOx trilayers. It is found that irradiation significantly decreases the depinning field of domain walls, allowing them to reach higher velocities at lower magnetic fields. It is also observed that larger He+ fluences lead to the formation of stable magnetic skyrmions with smaller sizes, in agreement with theoretical models for ultrathin films with labyrinthine domains.
Article
Physics, Applied
Yun Shu, Qianrui Li, Jing Xia, Ping Lai, Zhipeng Hou, Yonghong Zhao, Degang Zhang, Yan Zhou, Xiaoxi Liu, Guoping Zhao
Summary: The dynamics of isolated skyrmions in a ferromagnetic racetrack were computationally investigated. By modifying the edges and notch, a racetrack with different logic gates was designed with lower driving current density. Feasibility study at finite temperatures was also performed.
APPLIED PHYSICS LETTERS
(2022)
Article
Physics, Applied
Yun Shu, Qianrui Li, Jing Xia, Ping Lai, Zhipeng Hou, Yonghong Zhao, Degang Zhang, Yan Zhou, Xiaoxi Liu, Guoping Zhao
Summary: This study computationally investigates the dynamics of isolated skyrmions in a ferromagnetic racetrack with enhanced and modified edge properties. Based on the racetrack design, various skyrmion logic gates and diodes are realized with significantly reduced driving current density. The study also explores the impact of temperature on the feasibility of the design.
APPLIED PHYSICS LETTERS
(2022)
Article
Multidisciplinary Sciences
Christopher Klose, Felix Buettner, Wen Hu, Claudio Mazzoli, Kai Litzius, Riccardo Battistelli, Ivan Lemesh, Jason M. Bartell, Mantao Huang, Christian M. Guenther, Michael Schneider, Andi Barbour, Stuart B. Wilkins, Geoffrey S. D. Beach, Stefan Eisebitt, Bastian Pfau
Summary: Nanoscale magnetic fluctuations are observed beyond conventional resolution limits using coherent correlation imaging, allowing for the study of previously inaccessible magnetic phenomena. The method utilizes Fourier space analysis and an iterative hierarchical clustering algorithm to achieve high spatial and temporal resolution.
Correction
Physics, Multidisciplinary
Allan S. Johnson, Daniel Perez-Salinas, Khalid M. Siddiqui, Sungwon Kim, Sungwook Choi, Klara Volckaert, Paulina E. Majchrzak, Soren Ulstrup, Naman Agarwal, Kent Hallman, Richard F. Haglund, Christian M. Guenther, Bastian Pfau, Stefan Eisebitt, Dirk Backes, Francesco Maccherozzi, Ann Fitzpatrick, Sarnjeet S. Dhesi, Pierluigi Gargiani, Manuel Valvidares, Nongnuch Artrith, Frank de Groot, Hyeongi Choi, Dogeun Jang, Abhishek Katoch, Soonnam Kwon, Sang Han Park, Hyunjung Kim, Simon E. Wall
Article
Physics, Multidisciplinary
Allan S. Johnson, Daniel Perez-Salinas, Khalid M. Siddiqui, Sungwon Kim, Sungwook Choi, Klara Volckaert, Paulina E. Majchrzak, Soren Ulstrup, Naman Agarwal, Kent Hallman, Richard F. Haglund, Christian M. Guenther, Bastian Pfau, Stefan Eisebitt, Dirk Backes, Francesco Maccherozzi, Ann Fitzpatrick, Sarnjeet S. Dhesi, Pierluigi Gargiani, Manuel Valvidares, Nongnuch Artrith, Frank de Groot, Hyeongi Choi, Dogeun Jang, Abhishek Katoch, Soonnam Kwon, Sang Han Park, Hyunjung Kim, Simon E. Wall
Summary: Using time- and spectrally resolved coherent X-ray imaging, the researchers track the prototypical light-induced insulator-to-metal phase transition in vanadium dioxide on the nanoscale with femtosecond time resolution. They observe that the early-time dynamics are independent of the initial spatial heterogeneity and show a 200 fs switch to the metallic phase. Heterogeneous response emerges only after hundreds of picoseconds.
Article
Instruments & Instrumentation
J. Correa, M. Mehrjoo, R. Battistelli, F. Lehmkuehler, A. Marras, C. B. Wunderer, T. Hirono, V Felk, F. Krivan, S. Lange, I Shevyakov, V. Vardanyan, M. Zimmer, M. Hoesch, K. Bagschik, N. Guerrini, B. Marsh, I Sedgwick, G. Cautero, L. Stebel, D. Giuressi, R. H. Menk, A. Greer, T. Nicholls, W. Nichols, U. Pedersen, P. Shikhaliev, N. Tartoni, H. J. Hyun, S. H. Kim, S. Y. Park, K. S. Kim, F. Orsini, F. J. Iguaz, F. Buettner, B. Pfau, E. Ploenjes, K. Kharitonov, M. Ruiz-Lopez, R. Pan, S. Gang, B. Keitel, H. Graafsma
Summary: The PERCIVAL detector is a CMOS imager specifically designed for the soft X-ray regime. It has been used in various user experiments, such as ptychography, holographic imaging, and X-ray photon correlation spectroscopy. The detector has shown remarkable performance in terms of spatial resolution and frame rate, making it an attractive option for soft X-ray science.
JOURNAL OF SYNCHROTRON RADIATION
(2023)
Correction
Multidisciplinary Sciences
Christopher Klose, Felix Buttner, Wen Hu, Claudio Mazzoli, Kai Litzius, Riccardo Battistelli, Sergey Zayko, Ivan Lemesh, Jason M. M. Bartell, Mantao Huang, Christian M. Guenther, Michael Schneider, Andi Barbour, Stuart B. B. Wilkins, Geoffrey S. D. Beach, Stefan Eisebitt, Bastian Pfau
Article
Physics, Applied
R. Rouzegar, A. L. Chekhov, Y. Behovits, B. R. Serrano, M. A. Syskaki, C. H. Lambert, D. Engel, U. Martens, M. Muenzenberg, M. Wolf, G. Jakob, M. Klaeui, T. S. Seifert, T. Kampfrath
Summary: In this work, we significantly enhance the performance of an optically pumped spintronic terahertz emitter (STE) by optimizing the photonic and thermal environment. The terahertz pulses generated using high-energy pump pulses exhibit high electric fields and fluences comparable to those of a state-of-the-art terahertz source based on optical rectification. The optimized STE design retains the advantages of the standard design, but without the power loss associated with LiNbO3 setups, making it a promising tool for nonlinear terahertz spectroscopy. The emitted terahertz pulse using low-energy laser pulses shows a 2-fold improvement in electric field and covers a wider spectrum.
PHYSICAL REVIEW APPLIED
(2023)
Article
Optics
Martin Borchert, Dieter Engel, Clemens Von Korff Schmising, Bastian Pfau, Stefan Eisebitt, Daniel Schick
Summary: Time-resolved x-ray magnetic circular dichroism (XMCD) provides a unique spectroscopic technique to study spin and charge dynamics in multi-elemental magnetic materials. However, its application in the soft-x-ray range has been limited. Our development of a laser-driven plasma source combined with a magnetic thin-film polarizer enables XMCD spectroscopy at the Fe L edges in a laser laboratory for the first time. This approach can be extended to other absorption edges and allows for ultrafast magnetization studies with temporal resolution of < 10 ps.
Article
Chemistry, Physical
Kathinka Gerlinger, Bastian Pfau, Martin Hennecke, Lisa-Marie Kern, Ingo Will, Tino Noll, Markus Weigand, Joachim Graefe, Nick Traeger, Michael Schneider, Christian M. Guenther, Dieter Engel, Gisela Schuetz, Stefan Eisebitt
Summary: In this study, we demonstrate time-resolved scanning X-ray microscopy measurements using a tailored infrared pump laser at a scanning transmission X-ray microscope. By controlling the heat load on the sample, we can conduct destruction-free measurements at a high repetition rate. Our work provides new opportunities to study photo-induced dynamics on the nanometer scale, with access to picosecond to nanosecond time scales, which is of technological relevance, especially in the field of magnetism.
STRUCTURAL DYNAMICS-US
(2023)
Article
Instruments & Instrumentation
Martin Borchert, Julia Braenzel, Richard Gnewkow, Leonid Lunin, Themistoklis Sidiropoulos, Johannes Tuemmler, Ingo Will, Tino Noll, Oliver Reichel, Dirk Rohloff, Alexei Erko, Thomas Krist, Clemens von Korff Schmising, Bastian Pfau, Stefan Eisebitt, Holger Stiel, Daniel Schick
Summary: We present a laser-driven soft-x-ray plasma source with short pulse duration and wide spectral range. This source is used in two laboratory-scale beamlines for time-resolved magnetic resonant scattering, spectroscopy, and NEXAFS spectroscopy. Dedicated reflection zone plates are utilized as optical elements to capture, disperse, and focus the soft x rays, achieving high resolving powers and efficient data acquisition. Our setup enables soft-x-ray experiments that were not previously possible on a laboratory scale, making it a viable alternative to large-scale facilities.
REVIEW OF SCIENTIFIC INSTRUMENTS
(2023)
Article
Materials Science, Multidisciplinary
Anatolii E. Fedianin, Alexandra M. Kalashnikova, Johan H. Mentink
Summary: Exchange interactions determine the correlations between microscopic spins in magnetic materials. However, probing these spin correlations on ultrashort length and time scales is challenging due to the requirement of high spatial and temporal resolution. Recent experiments on laser-driven two-magnon modes in antiferromagnetic systems have raised questions about the underlying mechanisms and macroscopic manifestation of the observed spin dynamics. In this study, we use a simple microscopic model to derive the selection rules for cubic systems, which describe the polarization of laser pulses needed to excite and detect the dynamics of nearest-neighbor spin correlations. Our findings show that laser-driven spin correlations contribute to the optical anisotropy of the antiferromagnet, even in the absence of spin-orbit coupling.
Article
Physics, Multidisciplinary
Clemens von Korff Schmising, Somnath Jana, Kelvin Yao, Martin Hennecke, Philippe Scheid, Sangeeta Sharma, Michel Viret, Jean-Yves Chauleau, Daniel Schick, Stefan Eisebitt
Summary: The ultrafast response of CoFeB/Pt bilayers was studied by probing element-specific, core-to-valence-band transitions using high harmonic radiation in the extreme ultraviolet spectral range. Through magnetic scattering simulations and analysis of the energy- and time-dependent magnetic asymmetries, the element-specific response was accurately disentangled. It was found that the induced moment of Pt in the bilayer has a considerably smaller demagnetization time constant and much larger demagnetization amplitudes compared to the intrinsic moment of CoFeB.
PHYSICAL REVIEW RESEARCH
(2023)
