Controlling Curie temperature in (Ga,Ms)As through location of the Fermi level within the impurity band

Abstract

The ferromagnetic semiconductor (Ga,Mn)As has emerged as the most studied material for prototype applications in semiconductor spintronics. Because ferromagnetism in (Ga,Mn)As is hole-mediated, the nature of the hole states has direct and crucial bearing on its Curie temperature TC. It is vigorously debated, however, whether holes in (Ga,Mn)As reside in the valence band or in an impurity band. In this paper we combine results of channeling experiments, which measure the concentrations both of Mn ions and of holes relevant to the ferromagnetic order, with magnetization, transport, and magneto-optical data to address this issue. Taken together, these measurements provide strong evidence that it is the location of the Fermi level within the impurity band that determines TC through determining the degree of hole localization. This finding differs drastically from the often accepted view that TC is controlled by valence band holes, thus opening new avenues for achieving higher values of TC.

5 figures, supplementary material included

References in corpus (8)

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• Optical Properties of III-Mn-V Ferromagnetic Semiconductors
• Weak localization in GaMnAs: evidence of impurity band transport
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Cited by in corpus (14)

• Theory of Mn-doped I-II-V Semiconductors
• Observation of spontaneous spin-splitting in the band structure of an n-type zinc-blende ferromagnetic semiconductor
• High Curie temperatures at low compensation in the ferromagnetic semiconductor (Ga,Mn)As
• Ultrafast Probes of Nonequilibrium Hole Spin Relaxation in Ferromagnetic Semiconductor GaMnAs
• Ferromagnetism and impurity band in a new magnetic semiconductor: InMnP
• Generalized Multiband Typical Medium Dynamical Cluster Approximation: Application to (Ga,Mn)N
• Doping-dependent charge dynamics in CuxBi2Se3
• Electronic structure of (Ga,Mn)As revisited
• Spontaneous magnetization in presence of nanoscale inhomogeneities in diluted magnetic systems
• A comprehensive study of the magnetic, structural and transport properties of the III-V ferromagnetic semiconductor InMnP
• Response to the comment of K.W. Edmonds et al. on the article 'Controlling the Curie temperature in (Ga,Mn)As through location of the Fermi level within the impurity band'
• Correspondence on "Controlling the Curie temperature in (Ga,Mn)As through location of the Fermi level within the impurity band" by M. Dobrowolska et al
• Small quantum dots of diluted magnetic III-V semiconductor compound
• The Ferromagnetism in the Vicinity of Lifshitz Topological Transitions