Institution
Tohoku University
Education•Sendai, Japan•
About: Tohoku University is a education organization based out in Sendai, Japan. It is known for research contribution in the topics: Magnetization & Alloy. The organization has 72116 authors who have published 170791 publications receiving 3941714 citations. The organization is also known as: Tōhoku daigaku.
Topics: Magnetization, Alloy, Catalysis, Population, Magnetic field
Papers published on a yearly basis
Papers
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TL;DR: In this article, the thermopower in cobalt oxides generalizing the Heikes formula was studied and it was shown that the degeneracy, together with strong correlation of $3d$ electrons, causes the large energy consumption.
Abstract: We study theoretically the thermopower in cobalt oxides generalizing the Heikes formula. In the oxides, states of carriers are largely degenerate because the crystalline field and Hund's rule coupling compete in cobalt ions. It is shown that the degeneracy, together with strong correlation of $3d$ electrons, causes the large thermopower. The recent experiments in ${\mathrm{NaCo}}_{2}{\mathrm{O}}_{4}$ are discussed in the light of the theoretical result.
704 citations
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Seoul National University1, Kobe University2, University of Washington3, University of California, Irvine4, Chonnam National University5, University of Tokyo6, Kyoto University7, Tohoku University8, Stony Brook University9, Okayama University10, Boston University11, University of Warsaw12, Korea University13, Niigata University14, Dongshin University15, Massachusetts Institute of Technology16, Tokyo University of Science17
TL;DR: The K2K experiment observed indications of neutrino oscillation after 250 km flight of υμ. as mentioned in this paper The observed number of events in the data corresponding to 4.8 x 1019 protons on target is 56, while 80.1 5.4 + 6.2 is expected.
Abstract: The K2K experiment observed indications of neutrino oscillation after 250 km flight of υμ. The observed number of events in the data corresponding to 4.8 x 1019 protons on target is 56, while 80.1 5.4 +6.2 is expected. Both the decrease of the events and observed spectrum shape distortion are consistent with neutrino oscillation. The probability that the observations are statistical fluctuation of non oscillation is less than 1%. The allowed region of oscillation parameters is consistent with the one obtained from the atmospheric neutrino observation. After the accident of Super-Kamiokande (SK) detector, the reconstruction of SK has finished in 2002 and the K2K experiment resumed in December 2002.
702 citations
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TL;DR: In this paper, the authors used nanoscale pump-probe imaging to reveal the real-time dynamics of skyrmions driven by current-induced spin-orbit torques.
Abstract: Magnetic skyrmions are promising candidates for future spintronic applications such as skyrmion racetrack memories and logic devices. They exhibit exotic and complex dynamics governed by topology and are less influenced by defects, such as edge roughness, than conventionally used domain walls. In particular, their non-zero topological charge leads to a predicted ‘skyrmion Hall effect’, in which current-driven skyrmions acquire a transverse velocity component analogous to charged particles in the conventional Hall effect. Here, we use nanoscale pump–probe imaging to reveal the real-time dynamics of skyrmions driven by current-induced spin–orbit torques. We find that skyrmions move at a well-defined angle ΘSkH that can exceed 30° with respect to the current flow, but in contrast to conventional theoretical expectations, ΘSkH increases linearly with velocity up to at least 100 ms−1. We qualitatively explain our observation based on internal mode excitations in combination with a field-like spin–orbit torque, showing that one must go beyond the usual rigid skyrmion description to understand the dynamics. Experiments show that when driven by electric currents, magnetic skyrmions experience transverse motion due to their topological charge — similar to the conventional Hall effect experienced by charged particles in a perpendicular magnetic field.
702 citations
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01 Feb 2019TL;DR: In this article, the basic concepts of magnetic topological insulators and their experimental realization, together with the discovery and verification of their emergent properties are summarized. And the development of tailored materials through heterostructure engineering has made it possible to access the quantum anomalous Hall effect, topological magnetoelectric effect, the physics related to the chiral edge states that appear in these materials and various spintronic phenomena.
Abstract: The importance of global band topology is unequivocally recognized in condensed matter physics, and new states of matter, such as topological insulators, have been discovered. Owing to their bulk band topology, 3D topological insulators possess a massless Dirac dispersion with spin–momentum locking at the surface. Although 3D topological insulators were originally proposed in time-reversal invariant systems, the onset of a spontaneous magnetization or, equivalently, a broken time-reversal symmetry leads to the formation of an exchange gap in the Dirac band dispersion. In such magnetic topological insulators, tuning of the Fermi level in the exchange gap results in the emergence of a quantum Hall effect at zero magnetic field, that is, of a quantum anomalous Hall effect. Here, we review the basic concepts of magnetic topological insulators and their experimental realization, together with the discovery and verification of their emergent properties. In particular, we discuss how the development of tailored materials through heterostructure engineering has made it possible to access the quantum anomalous Hall effect, the topological magnetoelectric effect, the physics related to the chiral edge states that appear in these materials and various spintronic phenomena. Further theoretical and experimental research on magnetic topological insulators will provide fertile ground for the development of new concepts for next-generation electronic devices for applications such as spintronics with low energy consumption, dissipationless topological electronics and topological quantum computation. Magnetic topological insulators enable the investigation of the interplay between magnetism and topological electronic states. This Review summarizes the basic notions of magnetic topological insulators and the progress in the experimental realization of exotic topological phenomena.
701 citations
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TL;DR: In this paper, the transition of type thermoretrait of gels aqueux de N-isopropylamide (NIPA) de solutions de poly(NIPPA) and de PVME is studied.
Abstract: Etude par DSC de la transition de type thermoretrait de gels aqueux de N-isopropylamide (NIPA) de solutions de poly(NIPA) et de PVME. Comparaison des temperatures de transition des gels et des solutions obtenues par DSC avec les valeurs obtenues par mesure du gonflement des gels et par mesure des points de trouble des solutions. Interpretation des resultats a l'aide du concept d'interaction hydrophobe. Influence d'additifs de faible masse sur les temperatures de transition
701 citations
Authors
Showing all 72477 results
Name | H-index | Papers | Citations |
---|---|---|---|
John Q. Trojanowski | 226 | 1467 | 213948 |
Aaron R. Folsom | 181 | 1118 | 134044 |
Marc G. Caron | 173 | 674 | 99802 |
Masayuki Yamamoto | 171 | 1576 | 123028 |
Kenji Watanabe | 167 | 2359 | 129337 |
Rodney S. Ruoff | 164 | 666 | 194902 |
Frederik Barkhof | 154 | 1449 | 104982 |
Takashi Taniguchi | 152 | 2141 | 110658 |
Yoshio Bando | 147 | 1234 | 80883 |
Thomas P. Russell | 141 | 1012 | 80055 |
Ali Khademhosseini | 140 | 887 | 76430 |
Marco Colonna | 139 | 512 | 71166 |
David H. Barlow | 133 | 786 | 72730 |
Lin Gu | 130 | 868 | 56157 |
Yoichiro Iwakura | 129 | 705 | 64041 |