Syllabus for Magnetic Materials and devices
PHYS3116
Current Lecturer
Prof. Sheng Ju Email: jusheng@suda.edu.cn
Course Time
7th Semester
Lectures: 2 sessions/week, 50min /session. 18 weeks.
Course Description
This course will introduce and discuss the interesting magnetic effects found in the condensed matter system, which have two crucial ingredients. The first is about magnetic moments, including why the atoms have magnetic moments and how these magnetic moments can be affected by the local environments. The second is the interaction between these magnetic moments, including how the magnetic moments interact with each other and the different types of magnetic order found in the solid state.
Prerequisites
General Physics II (PHYS1026); Modern Physics (PHYS1027); Quantum Mechanics (PHYS3109)
Textbooks
Buschow K. H. J and F. R. De Boer, Physics of Magnetism and Magnetic Materials, 世界图书出版公司北京公司, 2013.
Main Contents
Week | Teaching Contents | Sessions | Objectives |
1 | Magnetic Moments | 2 | Magnetic moments and angular momentum; Precession; The Bohr magneton; Magnetization and field; classical mechanics and magnetic moments |
2 | Quantum mechanics of spin | 2 | Orbital and spin angular momentum; Pauli spin matrice and spinors; Raising and lowering operators; The coupling of two spins |
3 | Isolated magnetic moments | 2 | An atom in a magnetic field; Magnetic susceptibility; Diamagnetism |
4 | Paramagnetism | 2 | Semiclassical treatment of paramagnetism; Paramagnetism of J=1/2; The Brillioun function; Van Vleck paramagnetism |
5 | The ground state of an ion and Hund’s rules | 2 | Fine structure; Hund’s rule; L-S and j-j coupling |
6 | Crystal fields | 2 | Origin of crystal fields; Orbital quenching; The Jahn-Teller effect |
7 | Magnetic dipolar interaction | 2 | Magnetic dipolar interaction |
8 | Exchange interaction | 2 | Origin of exchange; Direct exchange |
9 | Mid-term exam | 2 |
|
10 | Superexchange | 2 | Indirect exchange in ionic solids: superexchange |
11 | Indirect exchange in metals | 2 | Indirect exchange in metals; Double exchange; anisotropic exchange interaction |
12 | Ferromagnetism | 2 | The Weiss model of a ferromagnet; Magnetic susceptibility; The effect of a strong magnetic field; Origin of the molecular field |
13 | Antiferromagnetism | 2 | Weiss model of an antiferromagnet; Magnetic susceptibility; The effect of a strong magnetic field; Types of antiferromagnetic order |
14 | Other magnetic order and structures | 2 | Ferrimagnetism; Helical order; Spin glasses |
15 | Phase transition | 2 | Broken symmetry; Models; phase transitions |
16 | Domains | 2 | Domain walls; Magnetocrystalline anisotropy; domain wall width; Domain formation; Magnetization processes; Small magnetic particles |
17 | Review | 2 | Review all the lecture materials |
Marking Scheme:
Homework | Quiz | Midterm | Final exam |
10% | 10% | 20% | 60% |
