Fundamentals of Solid-State Physics

Solid-state physics is the branch of physics that offers the widest range of phenomena for the application of both classical and quantum physics on macroscopic, microscopic, and atomic scales. Matter exists either in a solid state or a fluid state, and fluid is subdivided into liquid and gaseous states. In modern concept it is divided into condensed or gaseous states. Moreover, condensed matter is subdivided into the solid and liquid states. From the present point of view, these solids are conveniently divided into three classes (1) Crystalline, (2) Semi-crystalline (polycrystalline), and (3) Non-crystalline (Amorphous). Technology has benefited tremendously from the development of solid-state research. In general, instrumentation and measurement techniques incline heavily on methods and gadgetry initially developed for pure solid-state research. Today, much of technology is based on applying stable state phenomena. If that's what it is, then industrial physicists and material scientists should have some idea of the basic origin of these phenomena. Only this way can they expect to follow and direct the development of new materials and techniques. We can specifically mention the factors controlling the mechanical strength and stability of solids and the electrical and magnetic properties of solids. The present chapter, “Fundamentals of Solid-State Physics,” is planned with the following sequence of topics. We've already realized that solid-state physics includes a wide spectrum of subjects and materials, which is why one can choose more specific topics, for example, in terms of taste or professional experience. Nonetheless, they are fundamental and technical elements of magnetic and dielectric phenomena that demand to be included. Similarly, the surprising phenomena of superconductivity and unique theoretical interpretation justify its inclusion. This chapter also presents the current research developments in which major advances are still being made.