Figure 2: Resonant magnetic scattering patterns and radial integration of the intensity.
From: Laser-induced ultrafast demagnetization in the presence of a nanoscale magnetic domain network
(a,b) The resonant magnetic scattering patterns exhibit two well-defined bright spots indicating that the magnetic structure of the sample consists of aligned magnetic domains (the scale bars go from 0, white, to 750 CCD counts, orange; 16 CCD counts ~1 detected photon). Whereas the overall pattern remains the same for negative, panel (a), and positive, panel (b), delays, a clear decrease of the integrated intensity can be observed a few hundreds of femtosecond after an optical excitation. (c) Scattered intensity as a function of wave-vector transfer, q, for increasing time delays for a pump fluence of 7.5mJcm−2. The solid lines are fits by the same pseudo-Voigt profile scaled to take into account the evolution of the integrated intensity. The curves exhibit one peak centre at q0=0.04nm−1 with an FWHM, Δq0, of 0.006nm−1 corresponding to a mean magnetic domain width of about 80 nm. The high signal-to-noise ratio of these curves yields a very sensitive probe for the occurrence of spatial variations of the magnetic domain structure during the ultrafast demagnetization process.
