Giant Magnetoresistance Sensors Based on Ferrite Material and Its Applications

Abstract

In recent decades, new magnetic sensors based on giant magnetoresistance (GMR) have been studied and developed intensively. GMR materials have great potential for next-generation magnetic field sensing devices. The GMR material has many attractive features, for example, its electric and magnetic properties can be varied in a very wide range, low power consumption, and small size. Therefore, GMR material has been developed into various applications of sensor based on magnetic field sensings, such as magnetic field sensor, a current sensor, linear and rotary position sensor, data storage, head recording, nonvolatile magnetic random access memory, and biosensor. In this chapter, the recent development of a GMR thin-film-based ferrite material will be reviewed. Furthermore, recent and future trend application of GMR sensor will be discussed.

High Magnetic Field Sensitivity in Ferromagnetic–Ferroelectric Composite with High Mechanical Quality Factor

“…ME magnetic field sensors that comprise FM single crystals have been investigated owing to their excellent piezoelectric properties, demonstrating nT-to fT-level sensing limits [17][18][19]. These encouraging results demonstrate the feasibility of implementing small and efficient ME magnetic field sensor devices, which are comparable to conventional search coil and superconducting quantum interference device sensors [20] but do not require complicated fabrication processes or special equipment. However, the application of polycrystalline FE ceramics fabricated via an economical ceramic process would be more desirable from an industrial viewpoint, i.e., for mass production and to realize inexpensive sensor devices.…”

Prospect of Using Machine Learning-Based Microwave Nondestructive Testing Technique for Corrosion Under Insulation: A Review

“…GMR employs a ferromagnetic layer in which the electron orientation is easily manipulated by applying an external magnetic field [89]. In NDT, the GMR sensor is usually implemented as a magnetic receiver in the ECT technique to increase the sensitivity of small defect detections [90,91]. The magnetic moment of GMR sensor ferromagnetic layers is aligned with the secondary magnetic field generated by eddy currents, which overcomes antiferromagnetic coupling [92].…”

“…The use of supervised machine learning in the eddy currents with the GMR method has improved the accuracy of corrosion and corrosion-free regions classification [91,93]. The study utilizes Support Vector Machine (SVM), Naïve Bayes, logistic regression and random forests to classify the CUI and CUI-free areas to examine the corrosion in the coated cast-iron pipeline [93].…”

Ultrasensitive Magnetic Field Sensors for Biomedical Applications

“…The equivalent noise level has reduced down to a few pT/ √ Hz [80][81][82] in the low-frequency regime [23,83]. Nowadays, AMR [84], GMR [85], and TMR [86] sensors are the main technologies based on the magnetoresistance effect. The schematic images of sensing elements of AMR, GMR, and TMR magnetometers are presented in Figure 5.…”