Abstract Ultrafast non-thermal manipulation of magnetization by light relies on either indirect coupling the electric field component with spins via spin-orbit interaction or direct between magnetic and spins. Here we propose a scenario for optical modification exchange interaction, one strongest quantum effects strength 10 3 Tesla. We demonstrate that this isotropic opto-magnetic effect, which can be called inverse magneto-refraction, is allowed in material any symmetry. Its existence...

Abstract Traditionally, magnetic solids are divided into two main classes—ferromagnets and antiferromagnets with parallel antiparallel spin orders, respectively. Although normally the have zero magnetization, in some of them an additional antisymmetric spin–spin interaction arises owing to a strong spin–orbit coupling results canting spins, thereby producing net magnetization. The canted combine antiferromagnetic order phenomena typical ferromagnets hold great potential for spintronics...

Using a modal matching theory, we demonstrate the generation of short-range, chiral electromagnetic fields via excitation arrays staggered nanoslits that are in two dimensions. The near fields, which exhibit density greater than circularly polarized light, can enhance chiroptical interactions vicinity nanoslits. We discuss features nanostructure symmetry required to obtain and explicitly show how these structures give rise detection characterization materials with symmetry.

We report a theoretical formalism that describes dynamic magnetic response of rare-earth orthoferrites, particularly those with non-Kramers () ions, when driven by strong terahertz fields. derive total thermodynamic potential for the exchange coupled -Fe system constructing an effective Hamiltonian and employing mean-field theory approximation. investigate static properties Fe subsystems across spin-reorientation phase transitions obtain resonance frequencies sublattices as function...

Using the examples of laser-induced spin-reorientation phase transitions in ${\mathrm{TmFeO}}_{3}$ and ${\mathrm{ErFeO}}_{3}$ orthoferrites, we demonstrate that terahertz emission spectroscopy can obtain novel information about ultrafast spin dynamics, which is not accessible by more common all-optical methods. The power method evidenced fact that, addition to expected quasi-ferromagnetic quasi-antiferromagnetic modes iron sublattices, enables detection a resonance optically excited at an...

Magnon-polaritons are shown to play a dominant role in the propagation of terahertz (THz) waves through TmFeO3 orthoferrite, if frequencies vicinity quasi-antiferromagnetic spin resonance mode. Both time-domain THz transmission and emission spectroscopies reveal clear beatings between two modes with slightly above below this resonance, respectively. Rigorous modeling interaction spins light shows that correspond upper lower magnon-polariton branches. Our findings previously ignored...

Understanding how fast short-range interactions build up long-range order is one of the most intriguing topics in condensed matter physics. FeRh a test specimen for studying this problem magnetism, where microscopic spin-spin exchange interaction ultimately responsible either ferro- or antiferromagnetic macroscopic order. Femtosecond laser excitation can induce ferromagnetism FeRh, but mechanism and dynamics transition are intense debates. Employing double-pump THz emission spectroscopy has...

Simultaneous detection of terahertz (THz) emission and transient magneto-optical response is employed to study ultrafast laser-induced magnetization dynamics in three different types amorphous metallic alloys: Co, GdFeCo, NdFeCo. A satisfactory agreement between the revealed with help these two techniques obtained for Co GdFeCo. For NdFeCo THz indicates faster than response. This observation that addition spin Fe, laser excitation triggers Nd originating from its orbital momentum.

Using THz emission spectroscopy, we detect spin-photo-currents from a ferrimagnetic amorphous alloy GdFeCo to an adjacent Pt capping layer. The currents are generated upon excitation of GdFeCo/Pt heterostructure with femtosecond laser pulses. It is found that the polarization spin-polarized current determined by magnetic sublattice sensitivity rather than total magnetization, allowing for generation when net magnetization zero.

A nearly single cycle intense terahertz (THz) pulse with peak electric and magnetic fields of 0.5 MV/cm 0.16 T, respectively, excites both modes spin resonances in the weak antiferromagnet FeBO_{3}. The high frequency quasiantiferromagnetic mode is excited resonantly its amplitude scales linearly strength THz field, whereas low quasiferromagnetic via a nonlinear mechanism that quadratically field can be regarded as inverse Cotton-Mouton effect. optomagnetism shown to more energy efficient...

The microscopic origin of ultrafast modification the ratio between symmetric ($J$) and antisymmetric ($D$) exchange interaction in antiferromagnetic iron oxides is revealed, using femtosecond laser excitation as a pump terahertz emission spectroscopy probe. By tuning photon energy pulse we show that effect light on $D/J$ two archetypical ${\mathrm{FeBO}}_{3}$ ${\mathrm{ErFeO}}_{3}$ maximized when resonance with spin parity forbidden $d\ensuremath{-}d$ transition crystal-field split states...

Conventional wisdom dictates that magneto-optical and optomagnetic phenomena are reciprocal of equal strength. We test this assumption in a pump-probe experimental study the ultrafast inverse Faraday effect terbium gallium garnet crystal. The thorough quantitative analysis observed polarization response unambiguously demonstrates remarkable discrepancy several orders magnitude between strengths direct effects. This finding further questions validity standard magnetic models relying on use...

We show that femtosecond laser pulse excitation of the orthoferrite ${\mathrm{ErFeO}}_{3}$ triggers pico- and subpicosecond dynamics magnetic electric dipoles associated with low energy electronic states ${\mathrm{Er}}^{3+}$ ions. These are readily revealed by using polarization sensitive terahertz emission spectroscopy. It is shown changing one can excite either dipole-active or transitions between Kramers doublets ${^{4}I}_{15/2}$ ground state ($4{f}^{11}$) observations serve as a proof...

We report a theory of the effective permeability multilayered metamaterials containing thin ferromagnetic layers with magnetization pinned on either one or both surfaces. Because pinning and small film thickness, lowest frequency magnetic resonances are due to nonuniform exchange spin waves frequencies far above those expected for uniform resonance in known materials. Yet, coupling spin-wave modes electromagnetic field is shown be strong enough lead, parameters characteristic conventional...

Resonant optical pumping of $f\ensuremath{-}f$ electronic transitions in the ${\mathrm{Dy}}^{3+}$ subsystem with femtosecond laser pulses multisublattice antiferromagnet ${\mathrm{DyFeO}}_{3}$ produces a strongly pronounced effect on induced magnetization dynamics. Analyzing polarization and spectral properties emitted THz radiation, we infer that resonant magnetizes partially ordered ions time scale longitudinal change reaching almost $1%$. We also show for photon energies close to...

We investigate the magnonic properties of thin slabs one-dimensional crystals with aim obtaining a structure that possesses negative permeability at high frequencies. Metamaterials this kind could be used within devices based on refractive index phenomenon. calculate relative excitation strengths different spin-wave modes in crystals. find coupling between light and high-order can significant for specific design structure. These results suggest are therefore promising candidates metamaterials.

We present a method of calculation the effective magnetic permeability magnonic metamaterials containing arrays inclusions arbitrary shapes. The fully takes into account spectrum spin waves confined in inclusions. evaluate by considering particular case metamaterial formed stack identical two-dimensional (2D) periodic hexagonal disk-shaped nonmagnetic matrix. Two versions are considered. first approach is based on simple semianalytical theory that uses numerically calculated susceptibility...