Anisotropic magnetoresistance: materials, models and applications.

Area of Science:

• Condensed Matter Physics
• Materials Science
• Solid State Physics

Background:

• The resistance of conductive ferromagnets exhibits anisotropy relative to magnetization direction.
• This phenomenon, known as anisotropic magnetoresistance (AMR), shows differences in resistance when magnetization is parallel versus perpendicular to electric current.
• AMR has been observed and studied in both ferromagnets and, more recently, antiferromagnets.

Purpose of the Study:

• To provide a comprehensive review of the anisotropic magnetoresistance (AMR) effect.
• To examine the materials and physical mechanisms underlying AMR.
• To discuss the recent identification and study of AMR in antiferromagnets.

Main Methods:

• Literature review of the anisotropic magnetoresistance (AMR) phenomenon.
• Analysis of material properties and physical mechanisms contributing to AMR.
• Examination of studies on AMR in both ferromagnets and antiferromagnets.

Main Results:

• The resistance in certain ferromagnets is dependent on the relative orientation of magnetization and electric current.
• This anisotropic magnetoresistance (AMR) effect has been investigated for over a century.
• Recent research has extended the study of AMR to antiferromagnetic materials.

Conclusions:

• Anisotropic magnetoresistance (AMR) is a well-established phenomenon in ferromagnets with diverse applications.
• The understanding of AMR has expanded to include antiferromagnetic materials.
• AMR-based sensors are integral to various technologies, including automotive, aerospace, and biomedical imaging.