Symmetry-dependent ultrafast manipulation of nanoscale magnetic domains

Evidence of extreme domain wall speeds under ultrafast optical excitation

“…While ultrafast demagnetization is well established for a wide variety of ferromagnetic materials [15,16], only a few studies have hinted towards the ultrafast modifica-tion of nanoscale domain pattern [17][18][19]. These studies have used x-ray magnetic scattering to show that the diffraction rings obtained from labyrinthine domain pattern undergo ultrafast distortions of both ring radius and width.…”

“…These studies have used x-ray magnetic scattering to show that the diffraction rings obtained from labyrinthine domain pattern undergo ultrafast distortions of both ring radius and width. Tentative explanations have included domain wall broadening [17,20], and the ultrafast rearrangement of domains [18,19]. While these studies cannot clearly explain ultrafast distortions of diffraction patterns, domain rearrangement remains a viable hypothesis.…”

“…To test the prediction of extreme-speed wall motion, we conducted optical pump, EUV (extreme ultraviolet) magnetic scattering probe experiments with a mixedstate domain pattern that consists of domains of both labyrinthine and stripe-like character. Scattering from such samples yields two dominant diffraction components; an azimuthally uniform and a twin-lobed ring pattern [19]. We employed 2D fits similar to those in [19] to isolate and study the magnetization dynamics of domains of differing character.…”

“…Scattering from such samples yields two dominant diffraction components; an azimuthally uniform and a twin-lobed ring pattern [19]. We employed 2D fits similar to those in [19] to isolate and study the magnetization dynamics of domains of differing character. We measured the pump fluence dependence over an order of magnitude.…”

“…Magnetic multilayered sample with stack layering of (Ta(3 nm)/Cu(5 nm)/[Co 90 Fe 10 (0.25 nm) /Ni(1.35 nm)] × 8 /Co 90 Fe 10 (0.25 nm)/Cu(5 nm)/Ta(3 nm)) were used. The sample was grown using magnetron sputtering on 100 nm thick polycrystalline Si membranes and is the same sample as the one used in [19]. Magnetic force microscopy (MFM) studies prior to the experiment showed the presence of linearly oriented labyrinth domains with an average width of 110 nm.…”