Fundamental Curie temperature limit in ferromagnetic GaMnAs

Abstract

We provide experimental evidence that the upper limit of ~110 K commonly observed for the Curie temperature T_C of Ga(1-x)Mn(x)As is caused by the Fermi-level-induced hole saturation. Ion channeling, electrical and magnetization measurements on a series of Ga(1-x-y)Mn(x)Be(y)As layers show a dramatic increase of the concentration of Mn interstitials accompanied by a reduction of T_C with increasing Be concentration, while the free hole concentration remains relatively constant at ~5x10^20 cm^-3. These results indicate that the concentrations of free holes and ferromagnetically active Mn spins are governed by the position of the Fermi level, which controls the formation energy of compensating interstitial Mn donors.

14 pages, 3 figures

References in corpus (7)

• Hole-mediated ferromagnetism in tetrahedrally coordinated semiconductors
• Effects of annealing time on defect-controlled ferromagnetism in Ga1-xMnxAs
• Highly enhanced Curie temperatures in low temperature annealed (Ga,Mn)As epilayers
• Spin interactions of interstitial Mn ions in ferromagnetic GaMnAs
• Saturated Ferromagnetism and Magnetization Deficit in Optimally Annealed (Ga,Mn)As Epilayers
• Monte Carlo Study of Ferromagnetism in (III,Mn)V Semiconductors
• Do As antisites destroy the ferromagnetism of (Ga,Mn)As?

Cited by in corpus (25)

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• Prospects of high temperature ferromagnetism in (Ga,Mn)As semiconductors
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• Enhancement of Curie temperature in Ga(1-x)Mn(x)As/Ga(1-y)Al(y)As ferromagnetic heterostructures by Be modulation doping
• Electronic and magnetic properties of substitutional Mn clusters in (Ga,Mn)As
• Ferromagnetic resonance study of free hole contribution to magnetization and magnetic anisotropy in modulation-doped Ga${}_{1-x}$Mn${}_x$As/Ga${}_{1-y}$Al${}_y$As:Be
• Annealing-Dependent Magnetic Depth Profile in Ga[1-x]Mn[x]As
• Post-growth annealing of GaMnAs under As capping - an alternative way to increase Tc
• Tuning the ferromagnetic properties of hydrogenated GaMnAs
• The Effect of Mn Interstitials on the Lattice Parameter of Ga(1-x)Mn(x)As
• Growth and properties of ferromagnetic In(1-x)Mn(x)Sb alloys
• Intrinsic and Extrinsic Contributions to the Lattice Parameter of GaMnAs
• Photoreflectance Study of the Fundamental Optical Properties of (Ga,Mn)As Epitaxial Films
• Optical studies of carrier and phonon dynamics in Ga_{1-x}Mn_{x}As
• Role of Correlation and Exchange for Quasi-particle Spectra of Magnetic and Diluted Magnetic Semiconductors
• Anomalous Mn depth profiles for GaMnAs/GaAs(001) thin films grown by molecular beam epitaxy
• Effects of Capping on the (Ga,Mn)As Magnetic Depth Profile
• Suppression of hole-mediated ferromagnetism in GaMnP by hydrogen
• Half-metallic ferromagnetism in transition-metal doped germanium nitride: A first-principles study
• A new route to enhance the ferromagnetic transition temperature in diluted magnetic semiconductors
• p-type codoping effect in (Ga,Mn)As: Mn lattice location versus magnetic properties
• Atmospheric oxygen in Mn doped GaAs/GaAs(0 0 1) thin films grown by molecular beam epitaxy
• Electrical and optical studies of GaMnAs/GaAs(001) thin films grown by molecular beam epitaxy
• Hole compensation effect in III-Mn-V dilute ferromagnetic semiconductors