Nanosensors Based on Magnetic Materials

Sensors are becoming an integral part of the emerging digital era. These are basically transducer system that detects any change in physical parameters (force, magnetic field, humidity, electrochemical, biological change, etc.) and translate it into digital signals for the appropriate response or utilization of the change in physical parameters from an application perspective. The precision, reliability, sensitivity, and size of the sensors are key factors for effective utilization and applications. The integration of nanomaterials with sensor technology is an early-stage technology that makes sensors more flexible, compact in size, highly sensitive, and versatile with a dynamic range of measurement. Among the vast and multidisciplinary area of sensor technology, this chapter is focused on the fundamental understanding, design, and applications of the magnetic nanosensor based on: the Hall effect, Magnetoresistance (AMR, GMR, TMR), Nuclear magnetic resonance (NMR), and other properties of magnetic materials. This chapter deals with magnetic sensor technology, fundamental physics, materials, design, and its application as gas sensors, biosensors, and sensors for environmental monitoring applications.