Article
Optics
Yusef Maleki, Chaofan Zhou, M. Suhail Zubairy
Summary: This study presents the chiral transfer of quantum information in a metal nanoring network, enabling the transport and processing of chiral quantum states in nanorings by breaking the time-reversal symmetry. The direction of chirality can be controlled by preparing a quantum dot in its ground or excited state, achieving perfect or partial chiral transfer of excitation. The synthetic magnetic field used allows for the generation of specifically tailored nanoring states.
Article
Optics
P. Schiansky, T. Stroemberg, D. Trillo, V. Saggio, B. Dive, M. Navascues, P. Walther
Summary: In quantum mechanics, the reversibility of time evolution is based on the unitary nature. Recent experiments have demonstrated protocols for reverting unknown unitaries even in the case of unknown interactions with the target system, although these protocols are probabilistic. In this study, we show that quantum physics allows for deterministic time-reversal by taking advantage of the non-commuting nature of quantum operators. We present a recursive protocol with an arbitrarily high success probability for two-level quantum systems and achieve an average rewinding fidelity of over 95% using a photonic platform. Our protocol, which requires no knowledge of the quantum process to be rewound, is optimal in its running time and brings quantum rewinding into practical relevance.
Article
Materials Science, Multidisciplinary
N. O. Antropov, E. A. Kravtsov, M. V. Makarova, V. V. Proglyado, T. Keller, I. A. Subbotin, E. M. Pashaev, G. V. Prutskov, A. L. Vasiliev, Yu. M. Chesnokov, N. G. Bebenin, M. A. Milyaev, V. V. Ustinov, B. Keimer, Yu. N. Khaydukov
Summary: Research shows that by adjusting the exchange coupling in the structure, spin-flop transition (SFT) can be achieved in artificial ferrimagnets (FEMs) without the need for magnetic anisotropy. In experimental Fe-Gd FEMs, the transition field was successfully lowered by two orders of magnitude using Pd spacers.
Article
Physics, Multidisciplinary
N. Hachem, I. A. Badrour, A. El Antari, A. Lafhal, M. Madani, M. El Bouziani
Summary: The phase diagrams of a ferrimagnetic mixed-spin hexagonal Ising nanotube with Core-Shell structure were investigated using mean field approximation. The study reveals critical and compensation behaviors, as well as first-order phase transitions ending at isolated end-points in the ferrimagnetic phase domain at low temperatures.
CHINESE JOURNAL OF PHYSICS
(2021)
Article
Materials Science, Multidisciplinary
A. Harres, T. A. Mallmann, M. Gamino, M. A. Correa, A. D. C. Viegas, R. B. da Silva
Summary: This study experimentally investigates the magnetization reversal processes in amorphous CoFeB thin films of different thicknesses. It concludes that domain wall displacement is the dominant reversal mechanism for films with 200 nm and 300 nm, while coherent rotation becomes important near the hard axis for the thinnest sample even when the external magnetic field is applied away from it.
JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS
(2022)
Article
Physics, Applied
Paul Bouquin, Joo-Von Kim, Olivier Bultynck, Siddharth Rao, Sebastien Couet, Gouri Sankar Kar, Thibaut Devolder
Summary: In sub-100-nm-diameter magnetic tunnel junctions, magnetization reversal through domain-wall motion is shown to be dominated by two distinct stochastic effects: incubation delay related to domain-wall nucleation and stochastic motion in the Walker regime. Micromagnetics simulations reveal various factors contributing to temporal pinning of the wall near the disk center, such as vertical-Bloch line nucleation and wall precession. Reproducible ballistic motion is achieved when the Bloch and Neel wall profiles become degenerate in energy in optimally sized disks, enabling quasideterministic motion.
PHYSICAL REVIEW APPLIED
(2021)
Article
Chemistry, Physical
Qizhong Zhao, Fanghua Tian, Tieyan Chang, Kaiyan Cao, Dingchen Wang, Yin Zhang, Chao Zhou, Xiaoqin Ke, Wenliang Zuo, Yu Wang, Sen Yang, Xiaoping Song
Summary: In this study, the magnetization reversal phenomenon in the Ni20Mn3B6 alloy was investigated at low applied fields, revealing two compensation temperatures. The first temperature is attributed to competition between Mn atoms at different positions, while the second arises from moment rotation to satisfy Zeeman energy. This phenomenon enables tunable switching of magnetization between positive and negative values, providing potential applications in spintronic devices and magnetic storage materials.
JOURNAL OF ALLOYS AND COMPOUNDS
(2021)
Article
Chemistry, Multidisciplinary
T. Kaneyoshi
Summary: By decorating spin-3/2 atoms on the graphene-like Ising nanoparticle, the possibility of achieving a high critical temperature or a compensation point below the critical temperature is examined. The phase diagram and temperature dependences of magnetization in the decorated nanoparticle are investigated using effective-field approximation with correlations. It is shown how the paramagnetic graphene-like nanoparticle can transform into a magnetic ordering nanoparticle by changing the physical parameters of the decorated atom.
JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS
(2021)
Article
Physics, Multidisciplinary
Taiki Matsushita, Jiei Ando, Yusuke Masaki, Takeshi Mizushima, Satoshi Fujimoto, Ilya Vekhter
Summary: In this study, we investigate the spin-Nernst effect in time-reversal-invariant topological superconductors and present it as smoking-gun evidence for helical Cooper pairs. The spin-Nernst effect is a result of asymmetric scattering of quasiparticles at nonmagnetic impurities in spin space, generating a transverse spin current proportional to the temperature gradient. The magnitude and sign of this effect depend on the scattering phase shift at impurity sites, making it a unique and suitable method for identifying time-reversal-invariant topological superconducting orders.
PHYSICAL REVIEW LETTERS
(2022)
Article
Physics, Applied
Hao Chen, So Young Jeon, Sara A. Majetich
Summary: The effects of magnetostatic coupling on switching dynamics of patterned disc-shaped magnetic elements were investigated using micromagnetic simulations. The magnetization angle fluctuated more when neighboring dots had opposite magnetization directions, indicating a lower energy barrier for reversal.
JOURNAL OF PHYSICS D-APPLIED PHYSICS
(2022)
Article
Multidisciplinary Sciences
Yao Chen, Masahiro Sato, Yifei Tang, Yuki Shiomi, Koichi Oyanagi, Takatsugu Masuda, Yusuke Nambu, Masaki Fujita, Eiji Saitoh
Summary: Triplons are elementary spin excitations characteristic of dimerized magnets, playing a central role in spin properties, with their spin angular momentum flow leading to spin current.
NATURE COMMUNICATIONS
(2021)
Article
Nanoscience & Nanotechnology
Dong Li, Baoshan Cui, Xiaobin Guo, Zhengyu Xiao, Wei Zhang, Xiaoxiong Jia, Jinyu Duan, Xu Liu, Jie Chen, Zhiyong Quan, Guoqiang Yu, Xiaohong Xu
Summary: A current-induced four-state magnetization reversal under zero magnetic field has been achieved in a wedged Ta/MgO/CoFeB/MgO heterostructure with perpendicular magnetic anisotropy. The field-free multi-level reversal is determined by the spin-orbit torque effective field and the current-induced Oersted field, while the formation of intermediate Hall resistance states in multi-state switching depends strongly on current-induced Joule heating. These results provide a pathway for field-free multi-level state reversal, which is significant for developing non-volatile and energy-efficient multi-level memories or artificial neuron devices.
Article
Physics, Multidisciplinary
Udit Khanna, Yuval Gefen, Ora Entin-Wohlman, Amnon Aharony
Summary: Research has found that two-dimensional topological insulators can generate gapless edge modes at the edge, which may lead to finite conductivity. Additionally, it has been discovered that incompressible stripes exhibit broken translational invariance at integer fillings.
PHYSICAL REVIEW LETTERS
(2022)
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
Chunli Huang, Nemin Wei, Allan H. MacDonald
Summary: This study explores the quantized anomalous Hall effect in graphene multilayers with flat moire minibands, and suggests a current-driven mechanism for reversing the sign of the Hall effect in these Chern insulators.
PHYSICAL REVIEW LETTERS
(2021)