Magnetic Properties of Gadolinium-Doped ZnO Films and Nanostructures

Iman S. Roqan, Assa Aravindh Sasikala Devi, Singaravelu Venkatesh

Research output: Chapter in Book/Report/Conference proceedingChapter

Abstract

The magnetic properties of Gd-doped ZnO films and nanostructures are important to the development of next-generation spintronic devices. Here, we elucidate the significant role played by Gd-oxygen-deficiency defects in mediating/inducing ferromagnetic coupling in in situ Gd-doped ZnO thin films deposited at low oxygen pressure by pulsed laser deposition (PLD). Samples deposited at higher oxygen pressures exhibited diamagnetic responses. Vacuum annealing was used on these diamagnetic samples (grown at a relatively high oxygen pressures) to create oxygen- deficiency defects with the aim of demonstrating reproducibility of room-temperature ferromagnetism (RTFM). Samples annealed at oxygen environment exhibited super- paramagnetism and blocking-temperature effects. The samples possessed secondary phases; Gd segregation led to superparamagnetism. Theoretical studies showed a shift of the 4f level of Gd to the conduction band minimum (CBM) in Gd-doped ZnO nanowires, which led to an overlap with the Fermi level, resulting in strong exchange coupling and consequently RTFM.
Original languageEnglish (US)
Title of host publicationMagnetic Materials
PublisherIntechOpen
ISBN (Print)9789535124276
DOIs
StatePublished - Aug 24 2016

Fingerprint Dive into the research topics of 'Magnetic Properties of Gadolinium-Doped ZnO Films and Nanostructures'. Together they form a unique fingerprint.

Cite this