Publisher’s Note: Spin Pumping and Enhanced Gilbert Damping in Thin Magnetic Insulator Films [Phys. Rev. Lett.<b>111</b>, 097602 (2013)]

Kapelrud, André; Brataas, Arne

doi:10.1103/physrevlett.111.119902

Cited by 20 publications

(42 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Spin pumping is a versatile tool for probing spin dynamics in ferromagnets [1][2][3][4][5][6]. The magnitude of the pumped spin currents reveals information about the magnetization dynamics and the electron-magnon coupling at interfaces [7][8][9]. The precessing spins generate a pure spin flow into adjacent conductors.…”

mentioning

confidence: 99%

Spin pumping and inverse spin Hall voltages from dynamical antiferromagnets

Johansen

Brataas

2017

Phys. Rev. B

Self Cite

View full text Add to dashboard Cite

Dynamical antiferromagnets can pump spins into adjacent conductors. The high antiferromagnetic resonance frequencies represent a challenge for experimental detection, but magnetic fields can reduce these resonance frequencies. We compute the ac and dc inverse spin Hall voltages resulting from dynamical spin excitations as a function of a magnetic field along the easy axis and the polarization of the driving ac magnetic field perpendicular to the easy axis. We consider the insulating antiferromagnets MnF 2 , FeF 2 , and NiO. Near the spin-flop transition, there is a significant enhancement of the dc spin pumping and inverse spin Hall voltage for the uniaxial antiferromagnets MnF 2 and FeF 2 . In the uniaxial antiferromagnets it is also found that the ac spin pumping is independent of the external magnetic field when the driving field has the optimal circular polarization. In the biaxial NiO, the voltages are much weaker, and there is no spin-flop enhancement of the dc component. DOI: 10.1103/PhysRevB.95.220408 Spin pumping is a versatile tool for probing spin dynamics in ferromagnets [1][2][3][4][5][6]. The magnitude of the pumped spin currents reveals information about the magnetization dynamics and the electron-magnon coupling at interfaces [7][8][9]. The precessing spins generate a pure spin flow into adjacent conductors. Inside the conductor, the resulting spin accumulation and currents give insight into the spin-orbit coupling. The inverse spin Hall effect (ISHE) is often used to convert the pure spin current into a charge current, which is detected [10,11]. Additionally, the induced nonequilibrium spins can be probed with x-ray magnetic circular dichroism measurements [12,13].Antiferromagnets differ strikingly from ferromagnets [14]. There are no stray fields in antiferromagnets, making them more robust against the influence of external magnetic fields. The recent discovery of anisotropic magnetoresistance [15][16][17], spin-orbit torques [18], and electrical switching of an antiferromagnet [19] demonstrate the feasibility of antiferromagnets as active spintronics components.The real benefit of antiferromagnets is that they can enable terahertz circuits. Unlike ferromagnets, the resonance frequency of antiferromagnets is also governed by the tremendous exchange energy. We recently demonstrated that the transverse spin conductance, a governing factor of spin pumping, is as large in antiferromagnet-normal metal junctions (AF|N) as in ferromagnet-normal metal junctions [20]. Furthermore, this result is valid even when the magnetic system is insulating. The firm electron-magnon coupling at the interface opens the door for electrical probing of the ultrafast spin dynamics in antiferromagnets [20,21].Precessing spins in antiferromagnets generate terahertz currents in adjacent conductors. This ability opens new territory in high-frequency spintronics. Such studies could become influential in gathering vital insight into fast electron dynamics and eventually for a broad range of applications. These electric sign...

show abstract

mentioning

confidence: 99%

Spin pumping and inverse spin Hall voltages from dynamical antiferromagnets

Johansen

Brataas

2017

Phys. Rev. B

Self Cite

View full text Add to dashboard Cite

show abstract

“…This might not be the case in the antiparallel configuration, and results should be viewed with some caution. Spin waves have a wave-number-dependent damping enhancement [13], which implies that the dynamic coupling in spin valves should be mode dependent [23], which cannot be treated by our model. In the nonlinear regime and FIs with dimensions exceeding the exchange length l ex (∼17 nm for YIG), the energy separation between the modes may be coupled by the large-angle dynamics, increasing dissipation and reducing the oscillation amplitude [24], which again is outside the scope of the present study.…”

Section: Eigenmodes and Critical Currentsmentioning

confidence: 99%

“…For thin magnetic layers, even small torques can effectively modify the (Gilbert) damping, which can be observed as changes in the line width of the ferromagnetic resonance (FMR) spectra. We employ the macrospin model for the magnetization vectors that is applicable for sufficiently strong and homogeneous magnetic fields, while extensions are possible [13][14][15]. Our results include the calculation of effective (anti)damping resulting from in-plane charge currents in FI|N|FI trilayers, magnetic stability analysis in the current-magnetic field parameter space, and a brief analysis of the dynamics for currents above the critical value.…”

Section: Introductionmentioning

confidence: 99%

“…In this context, magnetic insulators such as yttrium iron garnet (YIG) combined with normal-metal contacts exhibiting spin-orbit interactions, such as Pt, have recently attracted considerable interest, both experimentally [2][3][4][5][6][7][8] and theoretically [9][10][11][12][13][14][15]. Since the discovery of nonlocal exchange coupling and giant magnetoresistance in spin valves, i.e., a normal metal sandwiched between two ferromagnetic metals, these systems have been known to display rich physics.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Current-induced magnetization dynamics in two magnetic insulators separated by a normal metal

2014

Self Cite

View full text Add to dashboard Cite

We study the dynamics of spin valves consisting of two layers of magnetic insulators separated by a normal metal in the macrospin model. A current through the spacer generates a spin Hall current that can actuate the magnetization via the spin-transfer torque. We derive expressions for the effective Gilbert damping and the critical currents for the onset of magnetization dynamics including the effects of spin pumping that can be tested by ferromagnetic resonance experiments. The current generates an amplitude asymmetry between the in-phase and out-of-phase modes. We discuss superlattices of stacked films of metals and magnetic insulators.

show abstract

“…where the factor of 2 stems from the Neumann (exchange) boundary condition for the magnetic fluctuations at the junction, which doubles the power of thermal noise and the associated pumping [17,18]. The dynamics of the order parameter n is governed by the stochastic LLG equation [19] …”

Section: -mentioning

confidence: 99%

Theory of the magnon-mediated tunnel magneto-Seebeck effect

et al. 2017

View full text Add to dashboard Cite

The tunnel magneto-Seebeck effect is the dependence of the thermopower of magnetic tunnel junctions on the magnetic configuration. It is conventionally interpreted in terms of a thermoelectric generalization of the tunnel magnetoresistance. Here, we investigate the heat-driven electron transport in these junctions associated with electron-magnon scattering, using stochastic Landau-Lifshitz phenomenology and quantum kinetic theory. Our findings challenge the widely accepted single-electron picture of the tunneling thermopower in magnetic junctions.

show abstract

Publisher’s Note: Spin Pumping and Enhanced Gilbert Damping in Thin Magnetic Insulator Films [Phys. Rev. Lett.111, 097602 (2013)]

Cited by 20 publications

References 0 publications

Spin pumping and inverse spin Hall voltages from dynamical antiferromagnets

Spin pumping and inverse spin Hall voltages from dynamical antiferromagnets

Current-induced magnetization dynamics in two magnetic insulators separated by a normal metal

Theory of the magnon-mediated tunnel magneto-Seebeck effect

Contact Info

Product

Resources

About