The extraordinary Hall effect in coherent epitaxial τ (Mn,Ni)Al thin films on GaAs

Publication Type

Journal Article

Authors

DOI

Abstract

Ultrathin coherent epitaxial films of ferromagnetic τ(Mn,Ni) 0.60Al0.40 have been grown by molecular beam epitaxy on GaAs substrates. X-ray scattering and cross-sectional transmission electron microscopy measurements confirm that the c axis of the tetragonal τ unit cell is aligned normal to the (001) GaAs substrate. Measurements of the extraordinary Hall effect (EHE) show that the films are perpendicularly magnetized, exhibiting EHE resistivities saturating in the range of 3.3-7.1 μΩ-cm at room temperature. These values of EHE resistivity correspond to signals as large as +7 and -7 mV for the two magnetic states of the film with a measurement current of 1 mA. Switching between the two magnetic states is found to occur at distinct field values that depend on the previously applied maximum field. These observations suggest that the films are magnetically uniform. As such, τ(Mn,Ni)Al films may be an excellent medium for high-density storage of binary information.

Journal

Journal of Applied Physics

Volume

73

Year of Publication

1993

ISSN

00218979

Research Areas