When liquid helium is cooled to an extremely low temperature, the liquid enters a superfluid state in which it flows without viscosity. This superfluid state is an example of a quantum phenomena appearing on the macroscopic level. This course will give an overview of the physics of superfluids, and go over how it can be understood and described as a quantum many-body problem.
Specifically, students will learn about the properties of the superfluid state, Bose-Einstein condensate, elemental excitation, the two-fluid model, two-dimensional superfluids, Fermi superfluidity, anisotropic superfluidity, etc.
By completing this course, students will be able to:
1) Study how the superfluidity, which is a macroscopic quantum phenomenon seen at low temperatures, can be explained in terms of a physics of quantum many-body problem.
2) Understand that liquid helium shows the superfluidity at very low temperatures, in which the helium behaves a fluid with zero viscosity.
3) Understand and explain how the physics of the superfluidity is described as a quantum effect on a macroscopic scale.
Bose-Einstein condensation, superfluidity, phase diagram, elementary excitation, two-fluid model
✔ Specialist skills | Intercultural skills | Communication skills | Critical thinking skills | ✔ Practical and/or problem-solving skills |
1) Classes are held on an independent topic each class, as listed in the course schedule.
2) Before coming to class, students should read the course schedule and check what topics will be covered. Required learning should be completed outside of the classroom for preparation and review purposes.
Course schedule | Required learning | |
---|---|---|
Class 1 | Phase diagram of helium | Explain the phase diagram of helium 3 and helium 4. |
Class 2 | Basic properties of superfluidity | Explain basic properties of superfluidity. |
Class 3 | Bose-Einstein condensation | Explain Bose-Einstein condensation |
Class 4 | Elementary excitation | Explain the relation between elementary excitations and superfluidity. |
Class 5 | Two-fluid model | Derive sound velocity in liquid helium based on two fluid model. |
Class 6 | Two dimensional superfluidity | Describe two dimensional superfluidity |
Class 7 | Fermionic superfluidity | Give examples of fermionic superfluidity and describe them. |
Class 8 | Anisotropic superfluidity | Give examples of anisotropic superfluidity and describe them. |
Course materials/textbooks is provided during class.
A. J. Leggett "Quantum Liquids" (Oxford University Press)
1) Students will be assessed on their understanding of anomalous properties of the superfluidity and their ability to describe/explain it in terms of the quantum many-body problem.
2) Students' course scores are based on report and final exams.
No prerequisites are necessary, but enrollment in the related courses is desirable.