0000000000082173

AUTHOR

Takeshi Nakagawa

0000-0002-6255-9358

showing 4 related works from this author

Giant magnetic anisotropy energy and coercivity in Fe island and atomic wire on W(110)

2012

We have directly investigated the giant magnetic anisotropy energy and coercivity of monolayer (ML) Fe islands and stripes on flat and stepped W(110) surfaces using x-ray magnetic circular dichroism. Both for islands and stripes, the magnetic anisotropy energy is $\ensuremath{\sim}$1.0 meV/atom, independent of the coverage below 0.5 ML. On the contrary, the coercive field of the islands rapidly drops from 4.3 T at 0.25 ML to 1.9 T at 0.50 ML, while that of the stripes moderately degrades from 3.5 T at 0.15 ML ($\ensuremath{\sim}$3 atom rows) to 3.0 T at 0.50 ML. We explain the contrastive behavior for the islands and stripes by different nucleation and remagnetization processes. Considering…

Magnetic anisotropyMaterials scienceNuclear magnetic resonanceCondensed matter physicsMagnetic circular dichroismProduct (mathematics)MonolayerAtomNucleationCoercivityCondensed Matter PhysicsEnergy (signal processing)Electronic Optical and Magnetic MaterialsPhysical Review B
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Energy- and angle-dependent threshold photoemission magnetic circular dichroism from an ultrathin Co/Pt(111) film

2010

Threshold photoemission magnetic circular dichroism (TPMCD) in one-photon photoemission (1PPE) and two-photon photoemission (2PPE) is measured at an ultrathin Co film grown on Pt(111). Energy-dependent measurements reveal maximum asymmetries directly at the photoemission threshold (1.90% for 1PPE and 11.7% for 2PPE) which weakly decrease with increasing photon energy. The measured TPMCD asymmetries are discussed in two excitation models on the basis of spin-resolved band-structure calculations. For the model of direct band-to-band transitions in other k directions than the direction of observation (Gamma-L) ab initio calculations for 1PPE and 2PPE are performed. The theory is in reasonable …

PhysicsCondensed Matter::Materials ScienceMagnetic circular dichroismAngle of incidence (optics)Ab initio quantum chemistry methodsInverse photoemission spectroscopyAngle-resolved photoemission spectroscopyFresnel equationsPhoton energyAtomic physicsCondensed Matter PhysicsExcitationElectronic Optical and Magnetic MaterialsPhysical Review B
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The Eurasian Modern Pollen Database (EMPD), version 2

2020

The Eurasian (née European) Modern Pollen Database (EMPD) was established in 2013 to provide a public database of high-quality modern pollen surface samples to help support studies of past climate, land cover, and land use using fossil pollen. The EMPD is part of, and complementary to, the European Pollen Database (EPD) which contains data on fossil pollen found in Late Quaternary sedimentary archives throughout the Eurasian region. The EPD is in turn part of the rapidly growing Neotoma database, which is now the primary home for global palaeoecological data. This paper describes version 2 of the EMPD in which the number of samples held in the database has been increased by 60% from 4826 to…

0106 biological sciencesLAKE CONSTANCE REGIONPalynology Palaeoecology Palaeoclimatology010504 meteorology & atmospheric sciencesHUMAN IMPACTrecent pollen deposition580 Plants (Botany)medicine.disease_cause01 natural sciences2417.10 Paleobotánicarecent pollen deposition[SDV.SA.SF]Life Sciences [q-bio]/Agricultural sciences/Silviculture forestryddc:550SURFACE POLLENSOUTHERN NORWAYSDG 13 - Climate ActionComputingMilieux_MISCELLANEOUSlcsh:Environmental sciencesSDG 15 - Life on Landlcsh:GE1-3500303 health sciencesCLIMATE-CHANGEGEAPUSENI NATURAL PARKlcsh:QE1-996.5Foundation (engineering)European pollen database[SDV.BV.BOT]Life Sciences [q-bio]/Vegetal Biology/Botanics[SDV.BIBS]Life Sciences [q-bio]/Quantitative Methods [q-bio.QM]EuropeLAST GLACIAL MAXIMUMGeographyNORTHERN IBERIAN PLATEAUpollenGE Environmental Sciences1171 Geosciences010506 paleontology[SDE.MCG]Environmental Sciences/Global ChangesEarth and Planetary Sciences(all)Library scienceClimate change[SDU.STU]Sciences of the Universe [physics]/Earth Sciences010603 evolutionary biologypollen; Europe; European pollen database; neotoma03 medical and health sciencesEurasian Modern Pollen Database2502.05 PaleoclimatologíaneotomaPollenmedicineSIERRA-NEVADA[SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces environment0105 earth and related environmental sciences030304 developmental biologyBotánicaHOLOCENE VEGETATION HISTORYDAS15. Life on land2416.03 Palinología[SDE.ES]Environmental Sciences/Environmental and Societylcsh:Geology[SDU]Sciences of the Universe [physics]MCPGeneral Earth and Planetary Sciences[SDE.BE]Environmental Sciences/Biodiversity and Ecology
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Dominance of the first excitation step for magnetic circular dichroism in near-threshold two-photon photoemission

2012

Magnetic circular dichroism (MCD) in near-threshold photoemission is measured for a perpendicularly magnetized Cs/Co/Pt(111) film with work function adjusted by Cs adsorption. For one-photon photoe ...

PhysicsMagnetic circular dichroismPhysics::OpticsCondensed Matter PhysicsElectronic Optical and Magnetic MaterialsCondensed Matter::Materials ScienceX-ray magnetic circular dichroismTwo-photon excitation microscopyCondensed Matter::SuperconductivityVibrational circular dichroismPerpendicularDominance (ecology)Work functionAtomic physicsExcitationPhysical Review B
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