Definitive Evidence of Interlayer Coupling Between (Ga,Mn)As Layers Separated by a Nonmagnetic Spacer

Abstract

We have used polarized neutron reflectometry to study the structural and magnetic properties of the individual layers in a series of (Al,Be,Ga)As/(Ga,Mn)As/GaAs/(Ga,Mn)As multilayer samples. Structurally, we observe that the samples are virtually identical except for the GaAs spacer thickness (which varies from 3-12 nm), and confirm that the spacers contain little or no Mn. Magnetically, we observe that for the sample with the thickest spacer layer, modulation doping by the(Al,Be,Ga)As results in (Ga,Mn)As layers with very different temperature dependent magnetizations. However, as the spacer layer thickness is reduced, the temperature dependent magnetizations of the top an bottom (Ga,Mn)As layers become progressively more similar - a trend we find to be independent of the crystallographic direction along which spins are magnetized. These results definitively show that (Ga,Mn)As layers can couple across a non-magnetic spacer, and that such coupling depends on spacer thickness.

Submitted to Physical Review B

References in corpus (7)

• Theory of ferromagnetic (III,Mn)V semiconductors
• Prospects of high temperature ferromagnetism in (Ga,Mn)As semiconductors
• Enhancement of Curie temperature in Ga(1-x)Mn(x)As/Ga(1-y)Al(y)As ferromagnetic heterostructures by Be modulation doping
• Interlayer Exchange Coupling in (Ga,Mn)As-based Superlattices
• Structural and magnetic properties of GaMnAs layers with high Mn content grown by Migration Enhanced Epitaxy on GaAs(100) substrates
• 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
• Ferromagnetism and interlayer exchange coupling in short period (Ga,Mn)As/GaAs superlattices

Cited by in corpus (5)

• Carrier-mediated antiferromagnetic interlayer exchange coupling in diluted magnetic semiconductor multilayers Ga${}_{1-x}$Mn${}_x$As/GaAs:Be
• In search of antiferromagnetic interlayer coupling in diluted magnetic thin films with RKKY interaction
• Interlayer and interfacial exchange coupling in ferromagnetic metal/semiconductor heterostructures
• Critical role of next-nearest-neighbor interlayer interaction in magnetic behavior of magnetic/nonmagnetic multilayers
• Electronic and optical spectra in a diluted magnetic semiconductor multilayer