0000000000727165

AUTHOR

Denise Hinzke

showing 4 related works from this author

Magnetic field control of the spin Seebeck effect

2015

The origin of the suppression of the longitudinal spin Seebeck effect by applied magnetic fields is studied. We perform numerical simulations of the stochastic Landau-Lifshitz-Gilbert equation of motion for an atomistic spin model and calculate the magnon accumulation in linear temperature gradients for different strengths of applied magnetic fields and different length scales of the temperature gradient. We observe a decrease of the magnon accumulation with increasing magnetic field and we reveal that the origin of this effect is a field dependent change of the frequency distribution of the propagating magnons. With increasing field the magnonic spin currents are reduced due to a suppressi…

PhysicsCondensed Matter - Materials ScienceField (physics)Condensed matter physicsSpin polarizationCondensed Matter - Mesoscale and Nanoscale PhysicsMagnonmagnetic field spin Seebeck effectMaterials Science (cond-mat.mtrl-sci)FOS: Physical sciencesCondensed Matter PhysicsElectronic Optical and Magnetic MaterialsMagnetic fieldCondensed Matter::Materials ScienceSpin wavepacs:75.40.MgMesoscale and Nanoscale Physics (cond-mat.mes-hall)Spin Hall effectSpin modelpacs:75.76.+jddc:530Condensed Matter::Strongly Correlated Electronspacs:75.30.DsSpin-½
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Length Scale of the Spin Seebeck Effect

2015

We investigate the origin of the spin Seebeck effect in yttrium iron garnet (YIG) samples for film thicknesses from 20 nm to 50  μm at room temperature and 50 K. Our results reveal a characteristic increase of the longitudinal spin Seebeck effect amplitude with the thickness of the insulating ferrimagnetic YIG, which levels off at a critical thickness that increases with decreasing temperature. The observed behavior cannot be explained as an interface effect or by variations of the material parameters. Comparison to numerical simulations of thermal magnonic spin currents yields qualitative agreement for the thickness dependence resulting from the finite magnon propagation length. This allow…

Length scaleMaterials scienceCondensed matter physicsSpin polarizationMagnonYttrium iron garnetGeneral Physics and Astronomypacs:72.25.-bCondensed Matter::Materials Sciencechemistry.chemical_compoundchemistrypacs:72.20.Papacs:75.40.GbSpin waveFerrimagnetismThermoelectric effectddc:530Condensed Matter::Strongly Correlated Electronspacs:75.30.DsSpin-½Physical Review Letters
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Thermally induced magnon accumulation in two-sublattice magnets

2016

We present a temperature-dependent study of the thermal excitation of a magnon accumulation in two-sublattice magnetic materials. Using atomistic spin model simulations, we study the local magnetization profiles sublattice-wise in the vicinity of a temperature step in antiferromagnets, as well as in ferrimagnets. It is shown that the strength of the magnon accumulation in these systems scales with the derivative of the magnetization with respect to the temperature. These results give an insight into the complex temperature dependence of the magnon accumulation by making a direct link to the macroscopic behavior of the magnetization.

PhysicsCondensed Matter - Materials ScienceSpin polarizationCondensed matter physicsMagnonMaterials Science (cond-mat.mtrl-sci)FOS: Physical sciences02 engineering and technology021001 nanoscience & nanotechnology01 natural sciencesCondensed Matter::Materials ScienceMagnetizationchemistry.chemical_compoundchemistryMagnet0103 physical sciencesThermalSpin modelddc:530Condensed Matter::Strongly Correlated Electrons010306 general physics0210 nano-technologyExcitationDerivative (chemistry)Physical Review B
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Determination of the origin of the spin Seebeck effect - bulk vs. interface effects

2013

The observation of the spin Seebeck effect in insulators has meant a breakthrough for spin caloritronics due to the unique ability to generate pure spin currents by thermal excitations in insulating systems without moving charge carriers. Since the recent first observation, the underlying mechanism and the origin of the observed signals have been discussed highly controversially. Here we present a characteristic dependence of the longitudinal spin Seebeck effect amplitude on the thickness of the insulating ferromagnet (YIG). Our measurements show that the observed behavior cannot be explained by any effects originating from the interface, such as magnetic proximity effects in the spin detec…

Condensed Matter - Other Condensed MatterCondensed Matter - Materials ScienceMaterials Science (cond-mat.mtrl-sci)FOS: Physical sciencesCondensed Matter::Strongly Correlated ElectronsOther Condensed Matter (cond-mat.other)
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