Magnetic Circular Dichroism Studies of Carrier-Induced Ferromagnetism in Ga12xMnx As
نویسندگان
چکیده
Magnetic circular dichroism is used to investigate the evolution of ferromagnetism in the p-type magnetic semiconductor Ga12xMnx As. Local Mn moments and holes produce two spectroscopically distinct contributions, whose properties reveal an antiferromagnetic Mn-hole alignment in the ferromagnetic state. These components are present in both metallic and insulating samples with different temperature and field dependences, suggesting that the holes play a more active role in mediating the ferromagnetic exchange than in traditional RKKY systems.
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