Quantitative magnetic imaging of thin films with reduced dimensions

Herrmann, Margit (2000) Quantitative magnetic imaging of thin films with reduced dimensions. PhD thesis, University of Glasgow.

Abstract

The work described in this thesis is based on the high spatial resolution magnetic imaging, which can be realised at the University of Glasgow on two transmission electron microscopes (TEMs). Both machines are highly modified to optimise magnetic imaging conditions. One is based on a JEOL 2000 FX and the other one on a Philips CM20 PEG microscope. Central to the thesis is the option to investigate samples in zero external field as well as to carry out in-situ magnetising experiments. The aim was to study the magnetisation reversal behaviour of two groups of magnetic thin films with reduced dimensions which are not only interesting in terms of fundamental micromagnetic studies but also for applications (field sensors, MRAM). The first group were so-called small magnetic elements (patterned thin films of permalloy) and the second group were Co/Cu multilayers. The main focus of investigation for the former group lay on the effects of structuring the edges of acicular elements whilst in the case of the Co/Cu multilayers the influence of different degrees of gas-damage was evaluated. Furthermore experimental data of the small magnetic elements was compared with simulation results of a commercially available software package (LLG Micromagnetics Simulator(TM)). In the results sections GMR measurements and MOKE hysteresis loops are presented before the investigation of the samples with several applied TEM investigation techniques is discussed. By these means the so-called biquadratic coupling was verified and quantified. In the final chapter this thesis concludes with the discussion of possible future experiments following on from this work. (Abstract shortened by ProQuest.).

• Item Type: Thesis (PhD)
• Qualification Level: Doctoral
• Subjects: Q Science > QC Physics
• Colleges/Schools: College of Science and Engineering > School of Physics and Astronomy
• Supervisor's Name: McVitie, Dr. S. and Chapman, Professor J.N.
• Date of Award: 2000
• Depositing User: Enlighten Team
• Unique ID: glathesis:2000-71230
• Copyright: Copyright of this thesis is held by the author.
• Date Deposited: 10 May 2019 10:49
• Last Modified: 02 Nov 2022 20:37
• Thesis DOI: 10.5525/gla.thesis.71230
• URI: https://theses.gla.ac.uk/id/eprint/71230