Preface

**Section 3**

and Biology

*by Satya Pal Singh*

*and Iseli L. Nantes-Cardoso*

*by Natela Zirakashvili*

*by Mohamed Abdelsabour Fahmy*

**Section 4**

**II**

*by Richard Pinčák and Erik Bartoš*

Spintronics **93**

**Chapter 7 95**

**Chapter 8 115**

**Chapter 9 133**

**Chapter 10 143**

Mechanics of Solid Deformable Bodies **163**

**Chapter 11 165**

**Chapter 12 187**

**Chapter 13 209**

Application of Spin-Orbit Coupling in Exotic Graphene Structures

The Ising Model: Brief Introduction and Its Application

*by Esakki Muthu Sankaran and Arumugam Sonachalam*

Technological Applications of Porphyrins and Related Compounds: Spintronics and Micro-/Nanomotors

2D Elastostatic Problems in Parabolic Coordinates

Boundary Element Mathematical Modelling and Boundary Element Numerical Techniques for Optimization of Micropolar Thermoviscoelastic Problems in Solid Deformable Bodies

Dynamic Stiffness Method for Vibrations of Ship Structures *by Xuewen Yin, Kuikui Zhong, Zitian Wei and Wenwei Wu*

*by David M. Lopes, Juliana C. Araujo-Chaves, Lucivaldo R. Menezes*

Exchange Bias Effect in Ni-Mn Heusler Alloys

In modern materials science, solid-state physics is a multidisciplinary field that describes the advancements in physics, chemistry, and material engineering. Solidstate physics deals with the behavior of solid matters in terms of physical metallurgy, quantum mechanism, crystallography, and electromagnetism. The concept of solid-state physics is currently being applied to all electronic parts, which is a boon for the electronics industry. The parts made up of solid matters are categorized as crystalline solids and amorphous materials/bulk metallic glasses/non-equilibrium materials. Solid-state materials exhibit interesting properties: higher strength, hardness, increased elastic strain limit, and outstanding corrosion and wear resistance. In addition, solid-state materials usually have unique physical, thermal, magnetic, and electrical properties, which are triggered to apply these materials to structural or functional applications. Furthermore, these materials possess macroscopically homogeneous, isotropic, and superior plastic deformation abilities. Therefore, to investigate and demonstrate the field of solid-state physics, this book addresses recent progress in the field of solid-state physics, which includes scientific works and reviews related to metastable and spintronics materials.

**Dr. Subbarayan Sivasankaran**

College of Engineering, Qassim University, Saudi Arabia

"Spintronics" usually refers to the branch of physics concerned with the manipulation, storage, and transfer of information by means of electron spins in addition to the electron charge in conventional electronics. It is very important to understand the principles and equations underlying the physics, transport, and dynamics of spin in solid-state systems. Major advances in electron spin transport started with the discovery of room temperature giant magnetoresistance, which paves the way towards application in spin-based practical devices such as spintronic field-effect transistors, spin-dependent tunneling diodes, logic gates, quantum computers, etc. The study of spintronics in semiconductors, metals, and other materials has been widely explored in its bulk form. The recent emergence of two-dimensional (2D) materials has been a real boom in the field of spintronics due to the strong spin– orbit coupling effect. The aim of the "Spintronics" section is to provide recent development in spintronics in bulk as well as 2D materials aimed at researchers, professors, post-doctorates, and graduate students in the discipline of physics, materials science, and nanotechnology and to help them master the overall knowledge of spintronics.

The section contains three chapters. In Chapter 1, the authors discuss spin—orbit coupling in an exotic graphene structure and also in biology. They introduce a new representation of the genetic code in the time series for string and D-brane

modeling by applying a spinor field to a superspace in time series data. This method develops supersymmetry for living organisms, which is considered to be one of the big puzzles of modern biology. Chapter 2 introduces the Ising model and its applications, and highlights developments in the field of magnetism relevant to the field of spintronics. In Chapter 3, the authors report the effect of Ni/Mn variation on the exchange bias properties in Mn-rich Ni50 – xMn37 + xSn13 (0 ≤ x ≤ 4) Heusler alloys. The exchange bias properties in the above system are the key elements of new spintronics systems.

I am very pleased to serve as section editor of this book, which contains a wide variety of studies from different authors. I would like to thank all the authors for their effort in contributing their research papers.

I would also like to acknowledge the help given by IntechOpen, in particular publishing manager Lada Bozic for her assistance, patience, and support throughout the whole process of this book project.

> **Dr. Pramoda Kumar Nayak** Department of Physics, IIT Madras, Chennai, India

problems in solid deformable bodies," was prepared by Assoc. Prof. Dr. Mohamed Abdelsabour Fahmy. The main objective of this chapter was to introduce a new theory called three-temperature nonlinear generalized micropolar thermoviscoelasticity. Because of strong nonlinearity of simulation and optimization problems associated with this theory, the numerical solutions for problems related to the proposed theory are always very difficult and require the development of new numerical techniques. So, the researcher proposed a new boundary element technique for simulation and optimization of such problems based on genetic algorithm, freeform deformation method, and nonuniform rational B-spline curve as the shape

The third chapter, "Dynamic stiffness method for vibrations of ship structures," is by Dr. Xuewen Yin, researcher Kuikui Zhong, researcher Zitian Wei, and Prof. Dr. Wen-wei Wu. The chapter was prepared by considering the dynamic stiffness method (DSM) in the solutions of the dynamics of ship structures. A DSM element accounting for both in-plane and bending vibrations in flat rectangular plates was developed, which makes it possible for modeling wave conversion across junctions in built-up plates. In addition, a DSM element for stiffened plates was formulated, which considers all possible vibrations in plates and beams, i.e. bending, torsion, and extension motions. The third type of DS plate element was examined in terms of fluid loading, which was induced by a vibrating plate. Finally, the proposed DSM method was extended to address vibration transmission in a built-up plate structure, which demonstrated the great potential of DSM in applications of more

> **Dr. Ezgi Günay** Associate Professor, Engineering Faculty,

> > Gazi University, Ankara, Turkey

Mechanical Engineering Department,

optimization technique.

**V**

practical and more general engineering fields.

This aim of this section is to explain the newly developed numerical and analytical methods by describing their solutions. Additionally in this section, newly developed theoretical studies on the solution methods of basic problems for solid mechanics are included. Solid mechanics problems are discussed in two main groups: solutions of beam, plate, and shell-type structures under static loading and solutions under dynamic loading. To make the mathematical problems simpler and more understandable, the modeling is performed in terms of plane stress, plane strain, and axisymmetric and symmetric conditions. The section "Mechanics of Deformable Bodies" contains three chapters. The section includes the basic scientific knowledge that is required as well as newly developed analytical solution methods and numerical solution techniques that have novel commercial application areas in engineering field.

The first chapter of the section "2D Elastostatic Problems in Parabolic Coordinates" was prepared by Assoc. Prof. Dr. Natela Zirakashvili and Prof. Dr. I. Vekua. The researchers explain and discuss the boundary value problems that were considered in the defined parabolic coordinate system. In the parabolic coordinates, the equilibrium equations, Hooke's law, and analytical (exact) solutions of 2D problems of elasticity were constructed in the homogeneous isotropic body bounded by coordinate lines of the parabolic coordinate system. Analytical solutions were obtained using the method of separation of variables. The solution was constructed using its general representation by two harmonic functions. Using MATLAB software, numerical results and constructed graphs of some boundary value problems were obtained and presented in detail.

The second chapter, "Boundary element mathematical modelling and boundary element numerical techniques for optimization of micropolar thermoviscoelastic problems in solid deformable bodies," was prepared by Assoc. Prof. Dr. Mohamed Abdelsabour Fahmy. The main objective of this chapter was to introduce a new theory called three-temperature nonlinear generalized micropolar thermoviscoelasticity. Because of strong nonlinearity of simulation and optimization problems associated with this theory, the numerical solutions for problems related to the proposed theory are always very difficult and require the development of new numerical techniques. So, the researcher proposed a new boundary element technique for simulation and optimization of such problems based on genetic algorithm, freeform deformation method, and nonuniform rational B-spline curve as the shape optimization technique.

The third chapter, "Dynamic stiffness method for vibrations of ship structures," is by Dr. Xuewen Yin, researcher Kuikui Zhong, researcher Zitian Wei, and Prof. Dr. Wen-wei Wu. The chapter was prepared by considering the dynamic stiffness method (DSM) in the solutions of the dynamics of ship structures. A DSM element accounting for both in-plane and bending vibrations in flat rectangular plates was developed, which makes it possible for modeling wave conversion across junctions in built-up plates. In addition, a DSM element for stiffened plates was formulated, which considers all possible vibrations in plates and beams, i.e. bending, torsion, and extension motions. The third type of DS plate element was examined in terms of fluid loading, which was induced by a vibrating plate. Finally, the proposed DSM method was extended to address vibration transmission in a built-up plate structure, which demonstrated the great potential of DSM in applications of more practical and more general engineering fields.

> **Dr. Ezgi Günay** Associate Professor, Engineering Faculty, Mechanical Engineering Department, Gazi University, Ankara, Turkey

modeling by applying a spinor field to a superspace in time series data. This method develops supersymmetry for living organisms, which is considered to be one of the big puzzles of modern biology. Chapter 2 introduces the Ising model and its applications, and highlights developments in the field of magnetism relevant to the field of spintronics. In Chapter 3, the authors report the effect of Ni/Mn variation on the exchange bias properties in Mn-rich Ni50 – xMn37 + xSn13 (0 ≤ x ≤ 4) Heusler alloys. The exchange bias properties in the above system are the key elements of

I am very pleased to serve as section editor of this book, which contains a wide variety of studies from different authors. I would like to thank all the authors for

I would also like to acknowledge the help given by IntechOpen, in particular publishing manager Lada Bozic for her assistance, patience, and support throughout the

This aim of this section is to explain the newly developed numerical and analytical methods by describing their solutions. Additionally in this section, newly developed theoretical studies on the solution methods of basic problems for solid mechanics are included. Solid mechanics problems are discussed in two main groups: solutions of beam, plate, and shell-type structures under static loading and solutions under dynamic loading. To make the mathematical problems simpler and more understandable, the modeling is performed in terms of plane stress, plane strain, and axisymmetric and symmetric conditions. The section "Mechanics of Deformable Bodies" contains three chapters. The section includes the basic scientific knowledge

that is required as well as newly developed analytical solution methods and numerical solution techniques that have novel commercial application areas in

The first chapter of the section "2D Elastostatic Problems in Parabolic Coordinates" was prepared by Assoc. Prof. Dr. Natela Zirakashvili and Prof. Dr. I. Vekua. The researchers explain and discuss the boundary value problems that were considered in the defined parabolic coordinate system. In the parabolic coordinates, the equilibrium equations, Hooke's law, and analytical (exact) solutions of 2D problems of elasticity were constructed in the homogeneous isotropic body bounded by coordinate lines of the parabolic coordinate system. Analytical solutions were obtained using the method of separation of variables. The solution was constructed using its general representation by two harmonic functions. Using MATLAB software, numerical results and constructed graphs of some boundary value problems were

The second chapter, "Boundary element mathematical modelling and boundary element numerical techniques for optimization of micropolar thermoviscoelastic

**Dr. Pramoda Kumar Nayak** Department of Physics,

> IIT Madras, Chennai, India

new spintronics systems.

engineering field.

**IV**

obtained and presented in detail.

whole process of this book project.

their effort in contributing their research papers.

Section 1

Solid State Behavior

**1**

Section 1
