Magnetoresistive Sensors for Nano-Ferric Particle Measurement

Abstract

Magnetoresistance has emerged as a promising technology in the field of sensors for localisation, identification, detection of biological, chemical, and physical materials. It has become an integral part of many biomedical and industrial applications. Currently, MR sensors like TMR are used for detecting minute nanoparticles due to their high sensitivity. But due to this sensitive nature, it is a complex process to set up and detect a magnetic field, as a solution to this problem several simulation techniques are developed that can accurately simulate an environment. The aim of the research is to understand the importance of simulation in making an experiment more efficient. A thorough investigation of the magnetoresistance based device is conducted and at the same time, a study on basic principles of magnetic tunneling junction is done.

Magnetic modelling is a useful tool to gain information on the hysteretic properties of magnetic systems. It helps in optimizing the design of sensors and helps in answering the magnetic interactions in micro and nanoscale. A TMR sensor can be effectively simulated with available data like material properties, material dimensions, and output signals can be obtained. The output signals give several values which can be used to understand the sensitivity of the device. This project focuses on modelling and simulation of TMR sensors using multiphysics modelling software (FEM method). The modelling software used is COMSOL Multiphysics® and magnetostatics physics modes are used to simulate the TMR sensor. At the same time, magnetic nanoparticles are simulated and the simulated TMR sensor is used to detect these magnetic nanoparticles. The concentration of nanoparticles is numerically calculated and further analysis is conducted. The conclusion drawn is that magnetoresistance based sensors can be simulated successfully using COMSOL Multiphysics® software and this simulation is helpful in detecting magnetic nanoparticles and the concentration of these nanoparticles are calculated. Furthermore, the future outlook and importance of material simulations are discussed.