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Kai Sun University of Michigan, Ann Arbor
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 TrainMechanical 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 SunEmail: [email protected]: 734-764-0730Office: 2245 RandallCourse Homepage: http://www-personal.umich.edu/~sunkai/teaching/Winter_2015/phys463.html
Time and placeTime: 8:30-10:00 am, Tuesdays and ThursdaysPlace: 335 West HallOffice hour: Wednesday 2:00-3:00pm at 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
PrerequisitePHYSICS 453 or equivalent
Problem Setsbi-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%
