How does a GMR sensor work?

In a GMR spintronic device, the first magnetic layer polarizes the electron spins. The second layer scatters the spins strongly if its moment is not aligned with the polarizer’s moment. When an external field overcomes the antiparallel coupling, the moments in the magnetic layers align and reduce the resistance.

What is the role of GMR sensor in magnetic HDD?

The main application of GMR is in magnetic field sensors, which are used to read data in hard disk drives, biosensors, microelectromechanical systems (MEMS) and other devices. GMR multilayer structures are also used in magnetoresistive random-access memory (MRAM) as cells that store one bit of information.

What is GMR in magnetic field?

The 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.

What is GMR and CMR?

From the beginning, it will become clear that a key difference between CMR and giant MR (GMR) is that the former deals with intrinsic effects of a material, and concomitant magnetic fields that are typically large compared with those needed for real applications.

How are giant magnetoresistance ( GMR ) sensors work?

How GMR Works Giant magnetoresistance (GMR) sensors produce a large change in resistance when the devices are subjected to a magnetic field. NVE Corporation is a leading provider of giant magnetoresistance (GMR) magnetic sensors.

What is the giant magnetoresistance ( GMR ) in condensed matter?

Giant Magnetoresistance (GMR) is a phenomenon of quantum mechanics and condensed matter physics. It is a kind of magnetoresistance effect that can be observed in thin film layers (several nanometers thick) between magnetic and non-magnetic materials.

What is the conducting layer of a GMR sensor?

A typical GMR medical sensor has a conducting layer approximately 3 nm (or one ten-millionth of an inch) thick. For reference, that is less than 10 atomic layers of copper, and less than one ten-thousandth the thickness of a piece of tissue paper.

What are the steps in making a GMR magnetometer?

A photomicrograph of a typical GMR magnetic sensor, also known as a magnetometer is shown below: The thin metal-alloy films are vacuum deposited onto silicon wafers. Other manufacturing steps include thermal annealing, magnetic annealing, and photolithography.