Book Chapters

Epitaxial Growth of Complex Metal Oxides - Defects in oxide crystals: nanoscale and interfacial effects

Woodhead Publishing

Charge transport in oxide crystals is strongly influenced by the existence of defects, especially oxygen vacancies, which are naturally present in these materials. In this chapter we discuss the importance of structural disorder in determining long range oxide ion conductivity. In particular, we analyze ion dynamics in some oxide crystals with pyrochlore and fluorite structures that are currently used as electrolytes in devices for energy generation. We will describe charge transport across grain boundaries in polycrystalline materials and the importance of space charge effects when the grain size is reduced to the nanometer range. Finally, we discuss how the accumulation of oxygen vacancies at the interfaces in thin film heterostructures can deeply modify performance and functionalities of electrochemical and oxide electronics devices.

Magnetic Tunnel Junctions: Spin Filtering by Interface-Induced Magnetism

Published by Jenny Stanford Publishing

This chapter shows that the spin reconstruction at the interfaces drives them into a novel magnetic state that acts as a spin filter. It considers the cases in which the origin of the induced magnetism is the superexchange interaction between B-site cations at both sides of the interface resulting from the bond reconstruction. The chapter suggests that the interfacial magnetism offers an interesting alternative route for the electric field control of the magnetism of the electrodes in a magnetic tunnel junction, a functionality, which is being actively pursued for the development of low-dissipation spintronics. It describes the use of the induced moment at the interface between cuprates and manganites to manipulate tunneling transport in magnetic tunnel junctions. Transport measurements of magnetic tunnel junctions have shown that the spin polarization at manganite interface decays faster than the bulk magnetization, suggesting the presence of an effective mechanism to reverse spins at the interfaces.

Dynamics of Glassy, Crystalline and Liquid Ionic Conductors: Experiments, Theories, Simulations

Published by Springer-Nature

El libro revisa el trabajo más relevante sobre dinámica de iones móviles en conductores iónicos, tanto experimental como teórico, intentando facilitar a los nuevos investigadores el acceso tanto a la historia de este campo de investigación como a sus actuales fronteras. El libro también puede utilizarse como material docente en cursos de grado y posgrado en instituciones académicas, dado que cubre desde los fundamentos de los conductors iónicos hasta sus diversas aplicaciones en distintos campos.