3.2 Solids and Nanostructures: Electrons, Spins, and Phonons
Project coordinator(s): C. von Korff Schmising, M. Wörner
Present topics

In this spectral range one can directly measure the electric field as a function of time. As an example, the figure shows the electric fields of three mid-infrared pulses A, B, and C after transmission through InSb for different delays between these pulses (a), (d) and the resulting nonlinear signals both in the time (b), (e) and the frequency (c), (f) domain.

Spatio-temporal map of the laser emission of a 450 nm emitting GaN-based broad-area diode laser (normalized). This snapshot was taken when one single 4.5-A current pulse, 800 ns in duration, has been applied. The spatial fluctuation is called filamentation of the nearfield. The local darkening that starts almost in center of the emitter at ~700 ns is result of a sudden degradation effect, called Catastrophic Optical Damage.

Extreme ultraviolet (XUV) radiation allows to access the element-specific magnetization via resonant magnetic circular dichroism. As an example, the graph shows distinct dichroic absorption of high harmonic radiation of a simple Co/Ni bilayer for two opposite magnetization directions (or equivalent left and right circularly ploarized XUV pulses). The ultrashort pulse structure and the small wavelengths of the XUV light allows measurements with femtosecond temporal and nanometre spatial resolution.