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arXiv · 1005.1494

Exchange constant and domain wall width in (Ga,Mn)(As,P) films with self-organization of magnetic domains

Sanaz Haghgoo·Murat Cubukcu·Hans Jürgen Von Bardeleben·Laura Thevenard·Aristide Lemaître·Catherine Gourdon
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Abstract

The incorporation of Phosphorus into (Ga,Mn)As epilayers allows for the tuning of the magnetic easy axis from in-plane to perpendicular-to-plane without the need for a (Ga,In)As template. For perpendicular easy axis, using magneto-optical imaging a self-organized pattern of up- and down-magnetized domains is observed for the first time in a diluted magnetic semiconductor. Combining Kerr microscopy, magnetometry and ferromagnetic resonance spectroscopy, the exchange constant and the domain wall width parameter are obtained as a function of temperature. The former quantifies the effective Mn-Mn ferromagnetic interaction. The latter is a key parameter for domain wall dynamics. The comparison with results obtained for (Ga,Mn)As/(Ga,In)As reveals the improved quality of the (Ga,Mn)As$_{1-y}$P$_y$ layers regarding domain wall pinning, an increase of the domain wall width parameter and of the effective Mn-Mn spin coupling. However, at constant Mn doping, no significant increase of this coupling is found with increasing P concentration in the investigated range.

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Sanaz Haghgoo, Murat Cubukcu, Hans Jürgen Von Bardeleben, Laura Thevenard, Aristide Lemaître, Catherine Gourdon. 2010-05-10. Exchange constant and domain wall width in (Ga,Mn)(As,P) films with self-organization of magnetic domains. https://doi.org/10.1103/physrevb.82.041301

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