Spin wave dynamics and the determination of intrinsic Gilbert damping in locally-excited Permalloy thin films

Time-resolved scanning Kerr effect microscopy has been used to study magnetization dynamics in Permalloy thin films excited by transient magnetic pulses generated by a micrometer-scale transmission line structure. The results are consistent with magnetostatic spin wave theory and are supported by micromagnetic simulations. Magnetostatic volume and surface spin waves are measured for the same specimen using different bias field orientations and can be accurately calculated by k-space integrations over all excited plane wave components. A single damping constant of Gilbert form is sufficient to describe both scenarios. The nonuniform pulsed field plays a key role in the spin wave dynamics, with its Fourier transform serving as a weighting function for the participating modes. The intrinsic Gilbert damping parameter $\alpha$ is most conveniently measured when the spin waves are effectively stationary.Comment: 5 pages, 4 figures, accepted by Phys. Rev. Let

Abstracts from the 8th International Conference on cGMP Generators, Effectors and Therapeutic Implications

This work was supported by a restricted research grant of Bayer AG

Laser based observation of space debris: Taking benefits from the fundamental wave

After the successful experimental demonstration of the prior published concept on laser-based monitoring of space debris in early 2012, we will present further technological and conceptual advancements of this position sensing scheme. The laser based measurement of LEO space debris positions in general offers the potential of a very high accuracy on the order of 10 meters in 3D, which in turn is the input for orbit processing of objects which are seemingly on collisional course. We argue that it is beneficial for the photon budget to make use of the so called fundamental wave, which is present in frequency doubled laser systems anyway. Thus, the here proposed move to near infrared wavelength is technologically easy to achieve and promising towards an operational laser-based debris ranging and tracking system

Mechanical Properties of Polydimethylsiloxane as a Function of the Amount and Type of Crosslinking Agent

Originally published at https://doi.org/10.3139/217.333