The domain-wall-induced reversal dynamics in compressively strained ${\text{Ga}}_{1-x}{\text{Mn}}_x\text{As}$ was studied employing the magneto-optical Kerr effect and Kerr microscopy. Due to the influence of a uniaxial part in the in-plane magnetic anisotropy $90°\pm \delta$ domain walls with considerably different dynamic behavior are observed. While the $90°+\delta$ reversal is identified to be propagation dominated with a small number of domains, the case of $90°-\delta$ reversal involves a larger number of nucleation centers. The domain-wall nucleation/propagation energies $ϵ$ for both transitions are estimated using model calculations from which we conclude that single domain devices can be achievable using the $90°+\delta$ mode.

• Received 3 July 2008

DOI:https://doi.org/10.1103/PhysRevB.78.155310