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arXiv · 0710.0479

Determination of the micromagnetic parameters in (Ga,Mn)As using domain theory

Catherine Gourdon·Alexandre Dourlat·Vincent Jeudy·Khashayar Khazen·Hans Jürgen Von Bardeleben·Laura Thevenard·Aristide Lemaître
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Abstract

The magnetic domain structure and magnetic properties of a ferromagnetic (Ga,Mn)As epilayer with perpendicular magnetic easy-axis are investigated. We show that, despite strong hysteresis, domain theory at thermodynamical equilibrium can be used to determine the micromagnetic parameters. Combining magneto-optical Kerr microscopy, magnetometry and ferromagnetic resonance measurements, we obtain the characteristic parameter for magnetic domains $λ_c$, the domain wall width and specific energy, and the spin stiffness constant as a function of temperature. The nucleation barrier for magnetization reversal and the Walker breakdown velocity for field-driven domain wall propagation are also estimated.

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Catherine Gourdon, Alexandre Dourlat, Vincent Jeudy, Khashayar Khazen, Hans Jürgen Von Bardeleben, Laura Thevenard, Aristide Lemaître. 2007-10-02. Determination of the micromagnetic parameters in (Ga,Mn)As using domain theory. https://doi.org/10.1103/physrevb.76.241301

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