Kai Sun
University of Michigan, Ann Arbor
Plan for today
Overview of solid state physics Course Syllabus
What is this course about?
Systems under study: Solids • What is a solid? • Solid is different from other states of matter by its
shear modulus (ability to resist the change of shape) • Examples: metal, stone, wood, plastics, glass, …
Methods: All we have learned! • Quantum mechanics • Electromagnetism • Statistical mechanics and thermodynamics • Mechanics • Various math tools (Fourier transform, eigen-problem, …)
How is this course different from others?
Previous courses (e.g., Mechanics, QM, E&M, Stat Mech,…) • Start from a few fundamental laws • Derive theorems from these laws • Verify the agreement with experiments
Solid state physics • Start by looking at real materials • Think about which laws/theorems apply here
(important step: make simplifications and approximations!) • Evaluate our model and think about how to do better • Prepares you for future research
What will we learn?
What are nucleons doing in a solid? What are electrons doing in a solid? What are spins doing in a solid? Topics of modern condensed matter Effects of disorder
What are nucleons doing in a solid?
Picture from wikipedia.com
Simple solids: crystals (we mostly deal with in this course)
Noncrystalline solids
(much more complicated to characterize)
• Why they exhibit such orders?
• How many types of crystal structures are there?
Nucleons don’t stay still at lattice sites!
At finite temperature: thermal fluctuations
• Vibrate around their equilibrium positions
• Interact with each other
Result: waves
Corresponding particles: Phonons
What are electrons doing in a solid?
Why are there two types of solids: conductors and insulators?
It is a quantum phenomenon
Superconductivity
The search for the best conductor: superconductor
Perfect conductivity (no resistance)
Picture from wikipedia.com
Superconductivity
Meissner effect: B=0
Magnetic levitation
Picture from wikipedia.com
Maglev train
Shanghai Maglev Train Mechanical force Magnetic force
No contact No friction Low noise High speed (300m/h)
What are spins doing in a solid?
Ferromagnetism 𝑀 ≠ 0
They play a very important role in the magnetism of solids
Paramagnetism 𝑀 = 0
𝑚
Magnetism (more exotic examples)
Anti-ferromagnetic:
Spin liquid:
Topics of modern condensed matter
Topological insulator
Conductor
Topological insulator: insulator inside but metal outside
Topological insulator
Why? Answer: Topology of the quantum wavefunction
Topics of modern condensed matter
Two different scales
High temperature superconductivity
Course Syllabus
Instructor: Prof. Kai Sun Email: [email protected] Phone: 734-764-0730 Office: 2245 Randall Course Homepage: http://www-personal.umich.edu/~sunkai/teaching/Winter_2013/phys463.html
Time and place Time: 8:30-10:00 am, Tuesdays and Thursdays Place: 335 West Hall Office hour: TBD (2245 Randall)
Course Syllabus
Textbook • Required textbook: Kittel, “Introduction to Solid State Physics” , 8th ed. • Additional reference (not required): Ashcroft and Mermin, Solid State Physics • Both books are on reserve at the library
Prerequisite PHYSICS 453 or equivalent
Problem Sets bi-weekly
Course work and grading
Course grade will be based on • Problem set: 20% • Final Presentation: 20%
You will form teams of up to 3 members. Each team will give a 15 minute presentation on a topic you choose, illustrating an application of solid state physics.
• Midterm: 30% • Final: 30%