Magnetic reorientation and thermal stability in MnAs/GaAs (100) micro patterns driven by size effects

Abstract

International audienceSize effects and their consequences in the thermal stability of the magnetization of the micro-sized MnAs/GaAs(100) ribbons were studied by magnetic force microscopy. We found out that the orientation in which size is reduced plays a key role in the magnetic configuration and thermal stability of the micro-sized patterns. On the one hand, when reducing the size in the [0001] alpha-MnAs direction, the system shows an improvement in the thermal stability of the remanent magnetization. On the other hand, when the size is reduced in the [11-20] alpha-MnAs direction, the system goes through a magnetic reconfiguration from in-plane magnetized to out-of-plane magnetized, which also improves the thermal stability. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4733698

Combined effects of vertical and lateral confinement on the magnetic properties of MnAs micro and nano-ribbons

“…As reported in Ref. 20 for thin films, three-dimensional arrangement of magnetic states ( Fig. 5(a)-region I), i.e., Landau, diamond, and doublediamonds, is observed for 2 w/t 4 and thickness varying from 160 nm down to 80 nm.…”

“…The surface magnetic domain configuration measured by XMCD-PEEM is related to the x-y plane view magnetic configuration of the ribbons. 20 Our simulations reproduce the progressive variation of the domain arrangement with w/t observed in our measurements and provide additional information about the domain structure phases for 0 w/t 35 and 10 nm t 160 nm. The domains were classified into six different phases, identified from I to VI (Figure 5(a)), taking into account the domain shapes ( Figure 5(b)), the magnetization uniformity along the ribbons thickness, y-z plane (Figure 5(c)), and domain wall types in the x-z easy plane ( Figure 5(d)).…”