quantum liquid crystal phases in strongly … · • required textbook: kittel, “introduction to...
TRANSCRIPT
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Kai Sun
University of Michigan, Ann Arbor
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Plan for today
Overview of solid state physics Course Syllabus
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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, …)
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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
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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
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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?
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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
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What are electrons doing in a solid?
Why are there two types of solids: conductors and insulators?
It is a quantum phenomenon
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Superconductivity
The search for the best conductor: superconductor
Perfect conductivity (no resistance)
Picture from wikipedia.com
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Superconductivity
Meissner effect: B=0
Magnetic levitation
Picture from wikipedia.com
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Maglev train
Shanghai Maglev TrainMechanical force Magnetic force
No contact No friction Low noise High speed (300m/h)
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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
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Magnetism (more exotic examples)
Anti-ferromagnetic:
Spin liquid:
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Topics of modern condensed matter
Topological insulator
Conductor
Topological insulator: insulator inside but metal outside
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Topological insulator
Why?Answer: Topology of the quantum wavefunction
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Topics of modern condensed matter
Two different scales
High temperature superconductivity
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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
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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
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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%