Autoren:	Becker, Sven
Titel:	Insulating magnetic oxides for spintronic applications
Online-Publikationsdatum:	7-Nov-2022
Erscheinungsdatum:	2022
Sprache des Dokuments:	Englisch
Zusammenfassung/Abstract:	Current technologies for data storage and information processing are heavily reliant on metallic, ferromagnetic materials. This hinders further improvement of devices due to a sensitivity to external perturbations, limits of processing speeds and excessive Joule heating from the passing charge currents. In this thesis, several promising material composites are explored for implementing magnonic logic operations. On a more fundamental side, interfacial effects are employed for probing the magnetic anisotropies and phase changes of a novel material system. Spin currents are discussed as an information carrier and for information processing. In magnetically ordered insulators, these spin currents are carried by magnons, the quanta of spin waves. The ferrimagnetic insulator Y3Fe5O12 (YIG) has shown to be able to transport magnons over large distances. However, for building devices based on magnons to implement key logic operations, one needs the possibility to actively manipulate the spin current. To this end, this thesis considers the experimental im- plementation of a magnon valve using bilayers of YIG and another magnetic garnet, Gd3Fe5O12. An alternative approach to implement improvements to spintronic devices is to replace the ferromagnetic material with an antiferromagnet, enabling writing speeds in the terahertz range. However, determining the state of an antiferromagnet is a major challenge necessitating the development of new techniques. One of these is spin Hall magnetoresistance (SMR), a surface-sensitive all-electrical measurement that probes the magnetic order of a material. In this thesis, SMR is utilized to probe the magnetic properties of the antiferromagnetically ordered compound TmFeO3 (TFO). First, a single crystal of TFO is investigated and its structural and magnetic properties are determined using bulk measurements. Using then only surface-sensitive SMR, we can attribute the electrical signals to the magnetic properties of the TFO. However, for device applications, bulk materials are not suitable. This motivates us to grow TFO as thin films, using pulsed laser deposition. The dependence of the mag- netic properties on the choice of substrate is demonstrated. These thin films possess similar properties to single crystals, as probed with volume-sensitive measurements. Performing then surface sensitive SMR measurements on these samples allows us to probe the magnetic properties of the TFO thin film in a more device relevant setting.
DDC-Sachgruppe:	500 Naturwissenschaften 500 Natural sciences and mathematics 530 Physik 530 Physics
Veröffentlichende Institution:	Johannes Gutenberg-Universität Mainz
Organisationseinheit:	FB 08 Physik, Mathematik u. Informatik
Veröffentlichungsort:	Mainz
ROR:	https://ror.org/023b0x485
DOI:	http://doi.org/10.25358/openscience-7957
URN:	urn:nbn:de:hebis:77-openscience-bd435f7c-6545-4b8d-aa5b-a0fa4e6feaa91
Version:	Original work
Publikationstyp:	Dissertation
Nutzungsrechte:	CC BY
Informationen zu den Nutzungsrechten:	https://creativecommons.org/licenses/by/4.0/
Umfang:	187 Seiten ; Illustrationen, Diagramme
Enthalten in den Sammlungen:	JGU-Publikationen