The precession of the magnetization a ferromagnet is shown to transfer spins into adjacent normal metal layers. This ``pumping'' slows down corresponding an enhanced Gilbert damping constant in Landau-Lifshitz equation. expressed terms scattering matrix ferromagnetic layer, which accessible model and first-principles calculations. Our estimates for permalloy thin films explain trends observed recent experiments.

Two complementary effects modify the GHz magnetization dynamics of nanoscale heterostructures ferromagnetic and normal materials relative to those isolated magnetic constituents: On one hand, a time-dependent pumps spin angular-momentum flow into adjacent and, on other angular momentum is transferred between ferromagnets by an applied bias, causing mutual torques magnetizations. These phenomena are manifestly nonlocal: they governed entire spin-coherent region that limited in size spin-flip...

A continuum model for the effective spin orbit interaction in graphene is derived from a tight-binding which includes $\pi$ and $\sigma$ bands. We analyze combined effects of intra-atomic spin-orbit coupling, curvature, applied electric field, using perturbation theory. recover Hamiltonian recently group theoretical arguments by Kane Mele. find, flat graphene, that intrinsic coupling $\Hi \propto \Delta^ 2$ Rashba due to perpendicular field ${\cal E}$, $\Delta_{\cal E} \Delta$, where...

In this paper, we study transport properties of non-equilibrium systems under the application light in many-terminal measurements, using Floquet picture. We propose and demonstrate that quantum can be controlled materials such as graphene topological insulators, via light. Remarkably, off-resonant light, induced; these exhibits Hall effects absence a magnetic field with near quantization conductance, realizing so-called without Landau levels first proposed by Haldane.

We study the magnetization dynamics in thin ferromagnetic films and small particles contact with paramagnetic conductors. A moving vector causes ``pumping'' of spins into adjacent nonmagnetic layers. This spin transfer affects similar to Landau-Lifshitz-Gilbert phenomenology. The additional Gilbert damping is significant for ferromagnets, when layers efficiently relax injected spins, but effect reduced a accumulation build-up normal metal opposes pumping. enhancement governed by (and, turn,...

Ferromagnetic insulators deposited on graphene can induce ferromagnetic correlations in graphene. We estimate that induced exchange splittings $\ensuremath{\Delta}\ensuremath{\sim}5\phantom{\rule{0.3em}{0ex}}\mathrm{meV}$ be achieved by, e.g., using the magnetic insulator EuO. study effect of spin transport properties. The proximity-induced determined from transmission resonances linear response conductance or, independently, by magnetoresistance measurements a spin-valve device....

We formulate a theory of spin dependent transport an electronic circuit involving ferromagnetic elements with non-collinear magnetizations which is based on the conservation and charge current. The considerably simplifies calculation properties complicated ferromagnet-normal metal systems. illustrate by considering novel three terminal device.

Precessing ferromagnets are predicted to inject a spin current into adjacent conductors via Ohmic contacts, irrespective of conductance mismatch with, for example, doped semiconductors. This opens the way create pure source (``spin battery'') by ferromagnetic resonance. We estimate and bias different material combinations.

A long-range dynamic interaction between ferromagnetic films separated by normal-metal spacers is reported, which communicated nonequilibrium spin currents. It measured resonance and explained an adiabatic spin-pump theory. In such a the mechanism of spatially magnetic moments leads to appreciable increase in resonant linewidth when fields are well apart, results dramatic narrowing approach each other.

Spin pumping and spin-transfer torques are two reciprocal phenomena widely studied in ferromagnetic materials. However, from antiferromagnets its relation to current-induced have not been explored. By calculating how electrons scatter off a normal metal-antiferromagnetic interface, we derive pumped spin staggered currents terms of the field, magnetization, their rates change. For both compensated uncompensated interfaces, is similar magnitude as ferromagnets with direction controlled by...

We investigate how spins relax in intrinsic graphene. The spin-orbit coupling arises from the band structure and is enhanced by ripples. orbital motion influenced scattering centers ripple-induced gauge fields. Spin relaxation due to Elliot-Yafet Dyakonov-Perel mechanisms fields combination with are discussed. In graphene, mechanism spin flip dominate spin-flip time inversely proportional elastic time. spin-relaxation anisotropy depends on an intricate competition between these mechanisms....

We consider the current-induced dynamics of insulating antiferromagnets in a spin Hall geometry. Sufficiently large in-plane currents perpendicular to Néel order trigger spontaneous oscillations at frequencies between acoustic and optical eigenmodes. The direction driving current determines chirality excitation. When exceeds threshold, combined effect pumping torques introduces dynamic feedback that sustains steady-state with amplitudes controllable via applied current. ac voltage output is...

A spin-pumping antiferromagnet Antiferromagnets have been used in spintronics mainly as a source of the so-called exchange bias. However, they hold promise for much more active role given that their magnetization dynamics can principle be faster than those ferromagnets. For this to materialize, antiferromagnets must learn tricks come naturally Vaidya et al. observed one such phenomenon called spin pumping (see Perspective by Hoffmann). The researchers irradiated MnF 2 with circularly...

The ability of magnetic materials to modify superconductors is an active research area for possible applications in thermoelectricity, quantum sensing, and spintronics. We consider the fundamental properties Josephson effect a class that recently have attracted much attention: altermagnets. show despite having no net magnetization band structure qualitatively different from ferromagnets conventional antiferromagnets without spin-split bands, altermagnets induce 0-π oscillations. decay length...

Recent works have predicted materials featuring bands with a large spin-splitting distinct from ferromagnetic and relativistically spin-orbit-coupled systems. Materials displaying this property are known as altermagnets feature spin-polarized band structure reminiscent of $d$-wave superconducting order parameter. We here consider the contact between an altermagnet superconductor determine how altermagnetism affects fundamental process Andreev reflection. show that resulting charge...

We propose a minimal toy model for two-dimensional altermagnet. The unravels altermagnetic properties at microscopic level. find spin-split electron and nondegenerate magnon bands with $d$-wave symmetry. use the to explore magnon-mediated superconductivity in altermagnets. dominant superconducting state is spin polarized $p$-wave adopts its characteristics from bands. Furthermore, we that critical temperature of altermagnets can be significantly enhanced by tuning chemical potential.

Recent theories of spin-current-induced magnetization reversal are formulated in terms a spin-mixing conductance ${G}^{\mathrm{mix}}.$ We evaluate ${G}^{\mathrm{mix}}$ from first principles for number (dis)ordered interfaces between magnetic and nonmagnetic materials. predict that the direction ferromagnetic insulator or one side tunnel junction multiterminal device can be switched even though negligible charge current is passed.

The interface-induced magnetization damping of thin ferromagnetic films in contact with normal-metal layers is calculated from first principles for clean and disordered Fe/Au Co/Cu interfaces. Interference effects arising coherent scattering turn out to be very small, consistent a small magnetic coherence length. Because the mixing conductances which govern spin transfer are good approximation real valued, pumping can described by an increased Gilbert factor but unmodified gyromagnetic...

We derive a phenomenological theory of current-induced staggered magnetization dynamics in antiferromagnets. The captures the reactive and dissipative torques conventional effects magnetic fields damping. A Walker ansatz describes dc domain-wall motion when there is no dissipation. If damping are included, remains robust moves slowly. As ferromagnets, velocity proportional to ratio between dissipative-torque In addition, current-driven antiferromagnetic acquires net moment.