Date of Graduation
2003
Document Type
Thesis
Degree Type
MS
Committee Chair
David Lederman
Abstract
MnxPt1-x/Co antiferromagnetic/ferromagnetic (AF/F) bilayers were grown via dc magnetron sputtering at room temperature on Si(111) and glass substrates. Samples were annealed in vacuum in a 1200 Oe magnetic field at various temperatures TA after growth. The Mn concentration x was determined from the MnPt lattice parameters and Rutherford backscattering spectroscopy. The maximum exchange bias (HE) was observed for x ~ 0.50 in agreement with previous work. Annealing caused the MnPt to form an ordered face-centered-tetragonal CuAu ordered structure which is necessary to observe HE. X-ray reflectivity indicates that an interdiffusion region exists at the MnPt/Co interface. The interdiffusion increases with TA, resulting in lower HE. The TA that maximizes HE, 318 °C, is a compromise between the volume fraction of MnPt forming the ordered CuAu structure, which increases HE, and the amount of interdiffusion, which decreases HE.
Recommended Citation
Morales Leal, Erie Hector, "Exchange bias in the manganese-platinum-cobalt system." (2003). Graduate Theses, Dissertations, and Problem Reports (ETD). 10774.
https://researchrepository.wvu.edu/etd/10774