A study of spin polarization in potential half-metals

Abstract

The study presented in this thesis has been concerned with measuring spin polarisation in magnetic materials using two methods: i) measurement of magnetoresistance in room temperature point contacts and ii) Point Contact Andreev Reflection (PCAR). Two novel techniques were developed to measure PCAR data. One of these involved the use of an eight-step lithographical fabrication process to produce lateral nanojunctions. The second involved the use of an atomic-force microscopy (AFM) tip to puncture a nanohole in a soft polymer layer. A superconducting nanocontact was then deposited through this nanohole.