1,456 research outputs found
Material and Thickness Investigation in Ferromagnet/Ta/CoFeB Trilayers for Enhancement of Spin–Orbit Torque and Field‐Free Switching
No full textSpin-orbit torques (SOTs) in ferromagnet (FM)/Ta/CoFeB trilayers are investigated as a function of Ta thickness. When the Ta is thinner than 1.5 nm, the sign of the SOT exerting on the top perpendicularly magnetized CoFeB depends on the bottom FM layer; it is positive for NiFe and negative for CoFeB. As the Ta thickness increases, the sign becomes negative irrespective of the bottom FM, indicating that SOTs are dominated by Ta, which has a negative spin Hall angle. SOT-induced switching without an in-plane magnetic field is observed in the thickness ranges where the bottom FM or FM/Ta interface-generated SOT is dominant. The results herein demonstrate that proper design of an FM/heavy metal combination and the material thickness can lead to an enhancement of the SOT efficiency and allow for field-free SOT switching.
Effects of proton and ion beam radiation on magnetic tunnel junctions
No full textConventional semiconductor-based electronic devices can cause errors when they are exposed to cosmic rays. Magnetic memory has been proposed as an alternative because it consists of a metal structure free from radiation-induced errors in principle. In this study, we investigated the effects of proton and Cr ion irradiations on the magnetic and electric properties of a magnetic tunnel junction (MTJ). We observed that the magnetic hysteresis and magnetoresistance of MTJ were not affected by proton irradiation of an energy of 20 MeV and dose levels up to 1 x 10(18)/m(2), thus demonstrating good radiation hardness in response to the proton beam. On the other hand, when a MTJ was irradiated by a Cr ion beam of an energy of 20 keV and dose levels up to 1 x 10(18)/m(2), its magnetic properties or magnetoresistance deteriorated, depending on the layer structure of the MTJ. A simulation study shows that this degradation may stem from radiation-energy dependent displacement damage in the magnetic layers, which can be avoided by the introduction of a proper protective layer.
Argument Structure and Unaccusativity in the Constraint-based Lexicon
No full textThis paper addresses the issue of Split Intransitivity (si) and Unaccusative Mis-matches (uMs), proposing a constraint-based approach to si and ums within a recent framework of Head-driven Phrase Structure Grammar. I argue against the widely accepted dichotomous distinction of intransitive verbs, which has been advanced by the Unaccusative Hypothesis [Perlmutter (1978)]. I then propose a quadripartitive distinction of intransitive verbs on the basis of the distribution of subject argument in the semantically motivated argument structure, and show that this quadriparti-tive distinction allows a better understanding of si and ums. The main idea of this proposal will be summarized as the Quadripartitive Split Intransitivity Hypothesis (Qsm). 1 The Problem It has long been observed cross-linguistically that intransitive verbs show some non-random grammatical heterogeneity. Ever since Perlmutter's Unaccusative Hypothesis [uH, Perlmutter (1978)], as formulated below in (1), later researchers have widely ac
Investigation of Radiation Effect on Magnetic Tunnel Junction against Proton and Ion Beam
No full text
Spin-orbit torques of three spin polarizations in magnetic trilayers
No full textThree spin polarizations of spin-orbit torques are theoretically available in ferromagnet/normal metal/ferromagnet trilayers. We report the quantification of spin-orbit torques of these spin polarizations via harmonic Hall voltage measurement. Furthermore, we show that using all three polarizations reduces the field-free spin-orbit torque (SOT) switching current of a perpendicular magnetization by employing a bottom ferromagnet with a tilted easy-axis in trilayer systems
Regulation of voltage-gated potassium channels attenuates resistance of side-population cells to gefitinib in the human lung cancer cell line NCI-H460
No full textBackground: Side-population (SP) cells that exclude anti-cancer drugs have been found in various tumor cell lines. Moreover, SP cells have a higher proliferative potential and drug resistance than main population cells (Non-SP cells). Also, several ion channels are responsible for the drug resistance and proliferation of SP cells in cancer. Methods: To confirm the expression and function of voltage-gated potassium (Kv) channels of SP cells, these cells, as well as highly expressed ATP-binding cassette (ABC) transporters and stemness genes, were isolated from a gefitinib-resistant human lung adenocarcinoma cell line (NCI-H460), using Hoechst 33342 efflux. Results: In the present study, we found that mRNA expression of Kv channels in SP cells was different compared to Non-SP cells, and the resistance of SP cells to gefitinib was weakened with a combination treatment of gefitinib and Kv channel blockers or a Kv7 opener, compared to single-treatment gefitinib, through inhibition of the Ras-Raf signaling pathway. Conclusions: The findings indicate that Kv channels in SP cells could be new targets for reducing the resistance to gefitinib.Y
Eine Argumentstruktur-basierte lexikalistische Analyse von unpersnlichen Medialkonstruktionen im Deutschen
No full textLicensing Nominals in the Multiple Nominative Constructions in Korean ? A Mereological Perspective
No full text- …
