Strain Engineering in Crystalline Solids

Abstract

Strain is one of the important physical entities in engineering materials. It beholds the underlying intertwined relations between various functionalities of crystalline materials that offers smart functionalities like pieozoelectricity, ferroelectricity, multiferroicity etc. Overall, this book is an attempt to discuss the operation of strain at different length scales and its influence on properties like electronic structure, structural stability, evolution of functional domains, etc. In addition procees induced strain and the respective microstructural evolution are also discussed. This chapter details the essential fundamentals that are required for the theoretical formalisms that are discussed in the later chapters of this book. Introductory sections on strain as a tensor and its interrelation with physical properties and its conformation to crystal symmetry through Neumann principle are discussed. In addition, discussions pertaining to strain as an equilibrium physical property is carried out in brief. A brief introduction to atomistic approach mainly through density functional theory is also presented with the needful basics of electrostatic potentials and illustrations. The last section of the chapter is dedicated to methods and measurements in which strain is involved in experimental studies. Most importantly, the commonly used processing of epitaxial strain and its experimental determination are discussed.