In this article, we report on the simulation and realization of a magnetic circuit allowing to apply an axial magnetic field higher than 1 Tesla. The proposed electromagnet is used to investigate the influence of a magnetic field on the polarization behavior of a vertical-cavity-surface-emitting laser (VCSEL). A nonlinear polarization behavior can be experimentally observed for currents as low ...

Nonlinear dynamics of the magnetic vortex state in a circular nanodisk was studied under a perpendicular alternating magnetic field that excites the radial modes of the magnetic resonance. Here, we show that as the oscillating frequency is swept down from a frequency higher than the eigenfrequency, the amplitude of the radial mode is almost doubled to the amplitude at the fixed resonance freque...

Nonlinear magnetization dynamics is essential for the operation of numerous spintronic devices ranging from magnetic memory to spin torque microwave generators. Examples are microwave-assisted switching of magnetic structures and the generation of spin currents at low bias fields by high-amplitude ferromagnetic resonance. Here we use X-ray magnetic circular dichroism to determine the number den...

In ferrofluids, external magnetic fields can produce a nonlinearity in the dependence of magnetic susceptibilities on the field strength, due to both normal saturation and abnormal saturation. We derive the nonlinear magnetic susceptibility by using a Langevin model. Then, we investigate the nonlinear ac responses of the magnetic susceptibility by means of a perturbation expansion method and an...

A theory for large amplitude compressional electromagnetic solitary pulses in a magnetized electron-positron (e-p) plasma is presented. The pulses, which propagate perpendicular to the external magnetic field, are associated with the compression of the plasma density and the wave magnetic field. Here the solitary wave magnetic field pressure provides the restoring force, while the inertia comes...

We present the experimental results based on a novel non-intrusive method for obtaining the magnetic field magnitude profile in a 6-kW Hall thruster operating at the nominal condition. We used the Xe I 6s’[1/2]1 → 6p’[3/2]2 transition at 834.912 nm (vacuum) to perform laser-induced fluorescence spectroscopy inside the channel near the exit plane. Due to the Zeeman effect, the obtained spectra c...

Magnetic fields appear to be present in all galaxies and galaxy clusters. Recent measurements indicate that a weak magnetic field may be present even in the smooth low density intergalactic medium. One explanation for these observations is that a seed magnetic field was generated by some unknown mechanism early in the life of the Universe, and was later amplified by various dynamos in nonlinear...

Nonlinear dielectric spectroscopy (NLDS) was used to detect interaction of a pulsed magnetic field (PMF) with membrane protein dynamics in aggregating Dictyostelium discoideum amoebae. In the experiments reported here, a strong nonlinear dielectric response of Dictyostelium discoideum cells is shown, and a distinctive nonlinear dielectric response of cells previously exposed to PMF is shown. Th...

Nonlinear longitudinal relaxation of a spin in a uniform external dc magnetic field is treated using a master equation for the quasiprobability distribution function of spin orientations in the configuration space of polar and azimuthal angles (analogous to the Wigner phase space distribution for translational motion). The solution of the corresponding classical problem of the rotational Browni...

– Absorption of surface acoustic waves by a two-dimensional electron gas in a perpendicular magnetic field is considered. The structure of such system at the filling factor ν close to 1/2 can be understood as a gas of composite fermions. It is shown that the absorption at ν = 1/2 can be strongly nonlinear, while small deviation form 1/2 will restore the linear absorption. The study of nonlinear...