Tuneable axis magnetic sensors

Overview

This sensor will overcome limitations in eddy current testing where it is necessary to measure signals which are orthogonal to a large applied field. It will also be of use in deconvolution of signals from multiple overhead conductors for fault detection. Our research will realise a wide impact for electricity networks, processing plants, pipeline infrastructure, and building integrity assessment.

Research into ion beam modification of thin films to develop novel voltage-tuneable magnetic sensors. This project is a collaboration between GNS Science and Robinson Research Institute at Victoria University of Wellington.

This programme aims to

• develop a magnetoresistive sensor with dynamic voltage-control of the sensing axis in a plane perpendicular to the layers
• develop the means for dynamic voltage-control of the sensing axis within the plane of the multilayers with the aim to dynamically voltage-control the sensing direction fully in three dimensions
• integrate a sensor with this dynamic control in non-destructive testing (NDT) tools

To achieve these objectives, we will

• modify the properties of surface materials to create magnetic sensors for non-destructive testing
• engineer optimal magnetic anisotropy via ion irradiation

The project

Creating new magnetic sensors

This project is undertaking ion beam implantation in single and multilayer films with the aim to modify the materials properties in magnetoresistance magnetic sensors and thereby achieve voltage tuning of the sensing axis. It is part of a larger programme headed by the Robinson Research Institute (RRI) with the aim of making new magnetic sensors for non-destructive testing to ensure infrastructure reliability.

Thin films will be made at RRI and GNS Science, which are both located in Wellington, New Zealand. Implantation will be undertaken at GNS Science and ion beam methods will be used to characterise the films. The structures will be further characterised by x-ray diffraction, SEM, and TEM. The magnetic and electronic properties will be researched up to 9 T and down to 2 K using our physical property measurement system (PPMS) and our magnetic property measurement system (MPMS).