Giant Magnetoresistance (GMR)


    In News

    • Researchers found that graphene displays an anomalous Giant magnetoresistance (GMR) at room temperature.

    What is Magnetoresistance & Giant Magnetoresistance (GMR)? 

    • Magnetoresistance is the tendency of a material to change the value of its electrical resistance in an externally-applied magnetic field.
    • Giant Magnetoresistance (GMR) is the large change in the electrical resistance which is induced by the application of a magnetic field to thin films composed of alternating ferromagnetic and nonmagnetic layers.
    • The 2007 Nobel Prize in Physics was awarded to Albert Fert and Peter Grünberg for the discovery of GMR.

    More about Study

    • The magnetoresistance observed in the graphene-based device was “almost 100 times higher than that observed in other known semimetals in this magnetic field range.” 
    • The team attributed this to the presence of a ‘neutral’ plasma and the electrons’ mobility.

    Applications of GMR

    • It is used in hard disk drives and magneto-resistive RAM in computers, biosensors, automotive sensors, micro-electromechanical systems, and medical imagers.
    • GMR-based devices are particularly used to sense magnetic fields.


    • Graphene is an allotrope of carbon consisting of a single layer of atoms arranged in a hexagonal lattice.
    • It has exceptionally high tensile strength, electrical conductivity, transparency, and thinnest two-dimensional material in the world. 
    • It is almost perfectly transparent since it only absorbs 2 percent of light.
    • Graphene is also known as a wonder material due to its vast potential in the energy and medical world.

    Applications of Graphene

    • Electronics: It has the potential to create the next-generation of electronics like Faster transistors, bendable phones etc.
    • Biomedical: ??Graphene’s unique properties allow for ground-breaking biomedical applications. Targeted drug delivery, improved brain penetration etc.
    • Battery: Graphene could dramatically increase the lifespan of a traditional lithium-ion battery i.e., devices can be charged quicker – and hold more power for longer.
    • Sensors: Ultra-sensitive sensors made from graphene could detect minute dangerous particles, helping to protect potentially dangerous environments.
    • Graphene Membranes: Graphene oxide membranes are capable of forming a perfect barrier when dealing with liquids and gasses. They have even been proven to stop helium, the hardest gas to block. 

    Source: TH