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Spatial Imaging of Magnetically Patterned Nuclear Spins in GaAs

J. Stephens·R. K. Kawakami·J. Berezovsky·M. Hanson·D. P. Shepherd·A. C. Gossard·D. D. Awschalom
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Abstract

We exploit ferromagnetic imprinting to create complex laterally defined regions of nuclear spin polarization in lithographically patterned MnAs/GaAs epilayers grown by molecular beam epitaxy (MBE). A time-resolved Kerr rotation microscope with approximately 1 micron spatial resolution uses electron spin precession to directly image the GaAs nuclear polarization. These measurements indicate that the polarization varies from a maximum under magnetic mesas to zero several microns from the mesa perimeter, resulting in large (10**4 T/m) effective field gradients. The results reveal a flexible scheme for lateral engineering of spin-dependent energy landscapes in the solid state.

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J. Stephens, R. K. Kawakami, J. Berezovsky, M. Hanson, D. P. Shepherd, A. C. Gossard, D. D. Awschalom. 2003-03-21. Spatial Imaging of Magnetically Patterned Nuclear Spins in GaAs. https://doi.org/10.1103/physrevb.68.041307

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