We study the switching behavior of thin single domain magnetic elements in the presence of microwave excitation. The application of a microwave field strongly reduces the coercivity of the elements. We show that this effect is most profound at the ferromagnetic resonance frequency of the elements. Observations using time-resolved magneto-optic Kerr microscopy in combination with pulsed microwav...

An ultrafast time-resolved magneto-optical pump probe is applied to study spin-relaxation processes in a ferromagnetic CoPt3 alloy film. Following spin-selective photoexcitation with circularly polarized femtosecond pulses, transient Kerr ellipticity tracks the evolution of the nonequilibrium spin system. We isolate two distinct processes: a subpicosecond component due to the relaxation of cohe...

The magnetization and resonance frequencies of submicron Fe magnetic dot arrays are investigated using Brillouin light scattering ~BLS! and magneto-optic Kerr Effect ~MOKE!. Large in-plane anisotropies, evident in both the BLS and MOKE results, are traced to shape anisotropies of the individual dots. The measured magnon frequencies are in good agreement with values calculated on the basis of is...

We describe a simple magneto-optical experiment and introduce a magneto-optical Kramers-Kronig analysis (MOKKA) that together allow extracting the complex dielectric function for left- and right-handed circular polarizations in a broad range of frequencies without actually generating circularly polarized light. The experiment consists of measuring reflectivity and Kerr rotation, or alternativel...

The complex off-diagonal components of conductivity tensor (g:, = 4, + i<,) of Co, a-Nd-Co and a-Y-Co was obtained by measuring magneto-optical Kerr effects, reflectivity and transmissivity in the range of fw = 0.8 eV 5eV. Nd-Co showed much greater wcr;, than Y-Co and the difference was deduced to be due to 4f T--t 5d 1. electron transition of Nd.

Kerr rotation measurements on a single electron spin confined in a charge-tunable semiconductor quantum dot demonstrate a means to directly probe the spin off-resonance, thus minimally disturbing the system. Energy-resolved magneto-optical spectra reveal information about the optically oriented spin polarization and the transverse spin lifetime of the electron as a function of the charging of t...

Previous magneto-optic Kerr effect studies of ultrathin epitaxial Fe films grown on stepped W( 001) surfaces yielded evidence of in-plane uniaxial magnetic anisotropy with magnetization perpendicular to the steps. We report spin-polarized secondary electron emission spectroscopy studies of the same system that confirms this novel micromagnetic phenomena, and provides a more detailed characteriz...

Magnetic anisotropy and magnetization reversal phenomena are studied in Ga12xMnxAs films grown on GaAs~001!. From the azimuthal dependence of the magneto-optical Kerr rotation and magnetic linear dichroism, the in-plane ^100& directions are unambiguously assigned as axes of easy magnetization. The values of the cubic and uniaxial anisotropies are determined. Magnetization reversal proceeds by n...

We introduce a new perspective on magnetoplasmonics in nickel nanoferromagnets by exploiting the phase tunability of the optical polarizability due to localized surface plasmons and simultaneous magneto-optical activity. We demonstrate how the concerted action of nanoplasmonics and magnetization can manipulate the sign of rotation of the reflected light's polarization (i.e., to produce Kerr rot...