Learn about the 7 most common types of magnetoresistance effects, including AMR, GMR, TMR, BMR, PHE, SMR, and REMR, and their applications.

7 Common Types of Magnetoresistance Effects

Magnetoresistance is a phenomenon in which the electrical resistance of a material changes in the presence of a magnetic field. It has many applications in various fields, including spintronics, magnetic storage, and sensors. In this article, we will discuss the seven most common types of magnetoresistance effects.

1. Anisotropic Magnetoresistance (AMR)

Anisotropic Magnetoresistance (AMR) is a type of magnetoresistance that occurs in ferromagnetic materials. In AMR, the resistance of a material changes as the direction of the magnetic field changes with respect to the crystal structure of the material. This effect arises due to the difference in the conductivity of electrons along and perpendicular to the magnetization direction.

2. Giant Magnetoresistance (GMR)

Giant Magnetoresistance (GMR) is a type of magnetoresistance that occurs in layered magnetic structures. In GMR, the resistance of a material changes as the magnetic field changes. This effect arises due to the spin-dependent scattering of electrons between the layers of the material. GMR is widely used in magnetic read heads for hard disk drives.

3. Tunnel Magnetoresistance (TMR)

Tunnel Magnetoresistance (TMR) is a type of magnetoresistance that occurs in magnetic tunnel junctions. In TMR, the resistance of a material changes as the magnetic field changes. This effect arises due to the spin-dependent tunneling of electrons through a thin insulating barrier between two ferromagnetic layers. TMR is widely used in magnetic random access memory (MRAM).

4. Ballistic Magnetoresistance (BMR)

Ballistic Magnetoresistance (BMR) is a type of magnetoresistance that occurs in ballistic conductors. In BMR, the resistance of a material changes as the magnetic field changes. This effect arises due to the spin-dependent deflection of electrons by the magnetic field in a ballistic conductor. BMR is a promising effect for spintronic devices.

5. Planar Hall Effect (PHE)

Planar Hall Effect (PHE) is a type of magnetoresistance that occurs in thin films. In PHE, the resistance of a material changes as the magnetic field changes. This effect arises due to the spin-dependent deflection of electrons by the magnetic field in a thin film. PHE is widely used in magnetic sensors.

6. Spin Hall Magnetoresistance (SMR)

Spin Hall Magnetoresistance (SMR) is a type of magnetoresistance that occurs in non-magnetic metals. In SMR, the resistance of a material changes as the magnetic field changes. This effect arises due to the spin Hall effect, which converts a charge current into a spin current in a non-magnetic metal. SMR is a promising effect for spintronic devices.

7. Rashba-Edelstein Magnetoresistance (REMR)

Rashba-Edelstein Magnetoresistance (REMR) is a type of magnetoresistance that occurs in two-dimensional electron gases with spin-orbit coupling. In REMR, the resistance of a material changes as the magnetic field changes. This effect arises due to the Rashba-Edelstein effect, which converts a charge current into a spin current in a two-dimensional electron gas with spin-orbit coupling. REMR is a promising effect for spintronic devices.

In conclusion, magnetoresistance effects are an important phenomenon with many applications in various fields. The seven types of magnetoresistance effects discussed in this article have different