Avalanches In Functional Materials And Geophysics

Avalanches in Functional Materials and Geophysics

This book provides the state-of-the art of the present understanding of avalanche phenomena in both functional materials and geophysics. The main emphasis of the book is analyzing these apparently different problems within the common perspective of out-of-equilibrium phenomena displaying spatial and temporal complexity that occur in a broad range of scales. Many systems, when subjected to an external force, respond intermittently in the form of avalanches that often span over a wide range of sizes, energies and durations. This is often related to a class of critical behavior characterized by the absence of characteristic scales. Typical examples are magnetization processes, plastic deformation and failure occuring in functional materials. These phenomena share many similarities with seismicity arising from the earth crust failure due to stresses that originate from plate tectonics.

Scanning Probe Studies of Structural and Functional Properties of Ferroelectric Domains and Domain Walls

This thesis explores the fascinating properties of domain walls in ferroelectric materials. Domain walls can be used as model systems to study fundamental aspects of interface physics, such as crackling noise, with implications extending to a broad variety of systems, from material fracture and earthquakes to solar flares and collective decision making. Ferroelectric domain walls also show functional properties absent from the domains themselves, such as enhanced conduction leading to the tantalizing possibility of reconfigurable nanoelectronic circuitry where domain walls are active components. This work discusses the crackling physics of domain walls in thin films of Pb(Zr0.2Ti0.8)O3, as well as links between the local conductivity of domain walls and nanoscale geometrical distortions due to defects, and discusses unusual polarization textures with rotational components at crossings of ferroelastic twin domains. The results presented in this thesis have important implications for the experimental study of crackling systems.

The New Frontier of Network Physiology: From Temporal Dynamics to the Synchronization and Principles of Integration in Networks of Physiological Systems