Unit information: Condensed Matter Physics 311 in 2020/21

Unit name	Condensed Matter Physics 311
Unit code	PHYS31111
Credit points	10
Level of study	H/6
Teaching block(s)	Teaching Block 2 (weeks 13 - 24)
Unit director	Professor. Hayden
Open unit status	Not open
Pre-requisites	120 credit points of units at level I/5 in Physics, Physics with Astrophysics, Theoretical Physics, joint honours Mathematics and Physics or Physics and Philosophy, or Chemical Physics programmes.
Co-requisites	None
School/department	School of Physics
Faculty	Faculty of Science

Description including Unit Aims

Lattice Dynamics: Adiabatic approximation. Vibrations of monoatomic and diatomic linear chain. Acoustic and optical modes. Quantization of lattice vibrations (phonons).

Lattice Thermal Properties: Density of states. Einstein and Debye models of the lattice specific heat. Debye temperature. Heat conduction by phonons and electrons.

Review of Fermi-Dirac statistics - spin particles. The Ideal Bose gas- integer spin particles. Bose-Einstein condensation. Application to ultracold atomic gases in traps.

The van der Waals gas. Maxwell's construction and gas-liquid critical point. Concept of a phase transition. Phase diagram of real substances, triple point. A brief introduction to Landau's theory of phase transitions. Order parameters, examples from magnetism and liquid crystals. Concept of critical exponent.

Aims:

To broaden knowledge of condensed matter physics particularly in the areas of lattice dynamics and phase transitions.

Intended Learning Outcomes

Know the nature of lattice excitations in a crystal and able to calculate simple thermal properties from the excitation spectra. Understand the Bose gas and its relevance to superfluidity in helium. Know the Maxwell construction and its significance for understanding phase transitions and triple points. Understand the gas-liquid and other critical points. Know the significance of order parameters with reference to simple examples in magnetism and liquid crystals. Know the concept of critical exponents.

Teaching Information

The unit will be taught through a combination of

• asynchronous online materials, including narrated presentations and worked examples
• synchronous group problems classes, workshops, tutorials and/or office hours
• asynchronous directed individual formative exercises and other exercises
• guided, structured reading

Assessment Information

Written, timed, open-book examination (100%)

Reading and References

• Chaikin and Lubensky Principles of Condensed Matter Physics (CUP)

• Kittel Introduction to Solid State Physics (Wiley & Sons)

• Ibach and Luth Solid State Physics (Springer-Verlag)