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dc.contributor.advisorMeystre, Pierreen_US
dc.contributor.authorWatson, Mathew David.
dc.creatorWatson, Mathew David.en_US
dc.date.accessioned2011-10-31T17:41:06Z
dc.date.available2011-10-31T17:41:06Z
dc.date.issued1991en_US
dc.identifier.urihttp://hdl.handle.net/10150/185544
dc.description.abstractDirect overwrite in magneto-optical recording is necessary to overcome the latency incurred by conventional erase before write recording on magneto-optical disks. In this work we theoretically analyze the thermomagnetic recording process on optical disks using a domain wall motion model. The wall motion model developed in this work can be used to examine overwrite schemes on both bilayer and single layer disks, that either rotate beneath an optical head or remain stationary. The model is directly compared with experiment for a GdTbFe direct overwrite sample, and is shown to produce results that are in agreement with experimental observations. We show that variations in the domain wall saturation velocity can mean the difference between writing or erasing a bit on the disk, and hence is a critical parameter in the recording process. We also show that direct overwrite by means of interior nucleation is highly unlikely. Rather, we show that the recording process involves a dynamic balance between those pressures which act to move the domain wall and those which act to freeze it into place. Finally we analyze the Nikon bilayer direct overwrite scheme, and then demonstrate an alternative bilayer overwrite scheme which avoids a major problem with the Nikon scheme.
dc.language.isoenen_US
dc.publisherThe University of Arizona.en_US
dc.rightsCopyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.en_US
dc.subjectDissertations, Academicen_US
dc.subjectOpticsen_US
dc.subjectElectrical engineering.en_US
dc.titleDirect overwrite in magnetooptical recording.en_US
dc.typetexten_US
dc.typeDissertation-Reproduction (electronic)en_US
dc.identifier.oclc711693274en_US
thesis.degree.grantorUniversity of Arizonaen_US
thesis.degree.leveldoctoralen_US
dc.contributor.committeememberMansuripur, Masuden_US
dc.contributor.committeememberBurke, James J.en_US
dc.identifier.proquest9136873en_US
thesis.degree.disciplineOptical Sciencesen_US
thesis.degree.disciplineGraduate Collegeen_US
thesis.degree.namePh.D.en_US
dc.description.noteThis item was digitized from a paper original and/or a microfilm copy. If you need higher-resolution images for any content in this item, please contact us at repository@u.library.arizona.edu.
dc.description.admin-noteOriginal file replaced with corrected file August 2023.
refterms.dateFOA2018-04-26T22:37:20Z
html.description.abstractDirect overwrite in magneto-optical recording is necessary to overcome the latency incurred by conventional erase before write recording on magneto-optical disks. In this work we theoretically analyze the thermomagnetic recording process on optical disks using a domain wall motion model. The wall motion model developed in this work can be used to examine overwrite schemes on both bilayer and single layer disks, that either rotate beneath an optical head or remain stationary. The model is directly compared with experiment for a GdTbFe direct overwrite sample, and is shown to produce results that are in agreement with experimental observations. We show that variations in the domain wall saturation velocity can mean the difference between writing or erasing a bit on the disk, and hence is a critical parameter in the recording process. We also show that direct overwrite by means of interior nucleation is highly unlikely. Rather, we show that the recording process involves a dynamic balance between those pressures which act to move the domain wall and those which act to freeze it into place. Finally we analyze the Nikon bilayer direct overwrite scheme, and then demonstrate an alternative bilayer overwrite scheme which avoids a major problem with the Nikon scheme.


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