Advances in the growth and characterization of magnetic, ferroelectric, and multiferroic oxide thin films

Abstract

The growth and characterization of functional oxide thin films that are ferroelectric, magnetic, or both at the same time are reviewed. The evolution of synthesis techniques and how advances in in situ characterization have enabled significant acceleration in improvements to these materials are described. Methods for enhancing the properties of functional materials or creating entirely new functionality at interfaces are covered, including strain engineering and layering control at the atomic-layer level. Emerging applications of these functional oxides such as achieving electrical control of ferromagnetism and the future of these complex functional oxides is discussed.

Ferroelectrically driven spatial carrier density modulation in graphene

“…1b) corresponds to a graphene sheet with multiple, parallel p-i junctions. This proof of concept could potentially be combined with advances in nanoscale domain engineering in ferroelectrics 32,33 or deterministic patterning 34 to create such periodic arrays with periodicities many orders of magnitude smaller than those demonstrated here, which could be particularly impactful for inducing and studying exotic phenomena in graphene.…”

Giant electrode effect on tunnelling electroresistance in ferroelectric tunnel junctions

“…F erroic nanostructures comprising materials such as ferromagnets and ferroelectrics and involving components with different levels of conductivity (metals, semiconductors and insulators) represent an important class of heterostructures that are very promising for applications in advanced electronic devices 1,2 . Indeed, the presence of order parameters in these nanostructures renders possible to switch their electrical resistances by external stimuli, which opens the way for memory, logic and neuromorphic computing applications [2][3][4] .…”

“…To demonstrate the feasibility of this explanation, we fitted the measured I-V curves in the range of small voltages using equation (1). The barrier heights f 1 and f 2 were regarded as adjustable parameters independent of applied voltage in the considered voltage range and the effective mass m b was assumed to be equal to the free electron mass m e (ref.…”

Crystallization engineering as a route to epitaxial strain control

“…However, one of the key aspects of such approaches is the formation of the strained/relaxed film directly during growth, which typically requires high temperatures and high or ultra-high vacuum. 6,7 A different approach has been proposed, 8 which is based on the low-temperature atomic layer deposition of the amorphous A-B-O film followed by its ex situ crystallization into the epitaxial perovskite ABO 3 on the lattice-matched substrate. The control of the epitaxial crystallization of such films offers a new pathway towards manipulating their strain state and, hence, functional properties.…”