Abstract
The in-plane magnetic anisotropy of (001) oriented InMnAs epitaxial films grown on InAs and GaSb were measured by magnetometry and the longitudinal magneto-optic Kerr effect. InMnAs epitaxial layers when grown on InAs exhibit a significant in-plane uniaxial anisotropy field of -0.66 kG at room temperature. The uniaxial magnetic anisotropy is attributed to differences in Mn atomic density along the [110] and [1- 10] directions, resulting from the uniaxial surface symmetry of the InAs (001) surface. The asymmetry of the Mn density is preserved in InMnAs films grown on InAs by a two-dimensional growth mechanism. However, disorder as evidenced by increasing surface pitting perturbs the growth from an ideal layer-by-layer mechanism. This results in a decrease in the magnitude of the uniaxial anisotropy field with increasing thickness between 320-630 nm. In contrast, InMnAs films grown on GaSb are magnetically isotropic for a thickness range of 50-420 nm. The isotropic behavior is attributed to three-dimensional island growth of films grown on GaSb that eliminates long range order.
| Original language | English (US) |
|---|---|
| Article number | 083907 |
| Journal | Journal of Applied Physics |
| Volume | 99 |
| Issue number | 8 |
| DOIs | |
| State | Published - 2006 |
Funding
The authors would like to thank Dr. Byron Watson and Weiqiang Mu at the MRSEC optics facility at Northwestern University for technical help with the MOKE magnetometer. This work was supported by the NSF under the Spin Electronics Program ECS-0224210 and the MRSEC program under Contract No. DMR-0076797.
ASJC Scopus subject areas
- General Physics and Astronomy