Tunable Planar Hall Effect in (Ga,Mn)(Bi,As) Epitaxial Layers

Area of Science:

• Condensed Matter Physics
• Materials Science
• Spintronics

Background:

• Dilute ferromagnetic semiconductors like (Ga,Mn)As are crucial for spintronic applications.
• Spin-orbit coupling significantly influences the magnetoelectric properties of these materials.
• Understanding modifications to these properties is key to advancing device performance.

Purpose of the Study:

• To investigate the effect of bismuth (Bi) incorporation on the planar Hall effect (PHE) in (Ga,Mn)As.
• To explore how Bi addition modifies spin-orbit coupling and magnetoelectric properties.
• To assess the potential of Bi-doped (Ga,Mn)As for spintronic devices.

Main Methods:

• Epitaxial growth of quaternary (Ga,Mn)(Bi,As) layers.
• Measurement of the planar Hall effect (PHE) under varying conditions.
• Analysis of magnetic properties, including coercive fields and anisotropy.

Main Results:

• A 1% Bi atomic fraction substitution increased the PHE magnitude by a factor of 2.5.
• Bi incorporation enhanced coercive fields and uniaxial magneto-crystalline anisotropy.
• Observed two-state PHE resistivity behavior tunable by magnetic field orientation.

Conclusions:

• Bismuth significantly enhances spin-orbit coupling in (Ga,Mn)As, modifying its magnetoelectric properties.
• The enhanced PHE and magnetic characteristics make (Ga,Mn)(Bi,As) a promising material for spintronics.
• Tunable two-state PHE behavior suggests potential for nonvolatile memory elements.