PYU33P15 Atomic Physics & Statistical Thermodynamics
Michaelmas Term – 30 lectures/tutorials – 5 credits (J Goold, G Cross)
From individual multi-electron atoms, electron interactions within the atom, and the resultant electronic structure of the atom, to ensembles of particles and their collective behaviour, this module provides a foundational overview of complex quantum behaviours and interactions.
Part I: Statistical Thermodynamics
Part II: Atomic Physics
On successful completion of this module, students should be able to:
· Describe the gross and fine structure of single-electron atoms in light of the semi-classical Bohr and quantum mechanical Schrödinger models
· Apply the laws of quantum mechanics to multi-electron atoms, taking into account the effects of angular momentum
· Explain molecular spectra in terms of vibrational, rotational and electronic transitions
· Outline the basic concepts of equilibrium statistical thermodynamics
· Describe mathematically the behaviour of physical systems governed by Fermi-Dirac, Bose-Einstein and Maxwell-Boltzmann statistics
· Determine the partition functions of simple quantum systems
Syllabus Part I: Statistical Thermodynamics
The purpose of this course is to introduce Statistical Thermodynamics, which provides a microscopic understanding of the macroscopic thermodynamic properties of materials. A simple assumption of equal statistical weights allows the properties of individual quantum particles to be combined together properly to calculate macroscopic thermodynamic quantities, which can be compared with experiment. Topics covered (1) Counting states in classical and quantum systems (2) Fundamental assumption of statistical physics; ensembles (3) Model system of 2-state components (4) Two systems in equilibrium: entropy, temperature and chemical potential (5) Partition functions and their relation to thermodynamic quantities (6) Third Law of Thermodynamics (7) Fermi-Dirac and Bose-Einstein Statistics (8) Quasi-classical statistics: equipartition of energy (9) Application of quantum statistics to photons, gases, and solids.
Part II: Atomic and Molecular Spectroscopy
One-electron and multi-electron atoms, orbital and spin angular momentum, shell structure, Aufbau principle, electric and magnetic moments, spin-orbit coupling and fine structure, Lamb shift, addition of angular momenta, term symbols, electric dipole and quadrupole and magnetic dipole selection rules, atomic energy levels and spectroscopies in electric and magnetic fields, linewidths, chemical binding in molecules, rotational, vibrational and electronic spectroscopies of molecules, traps, condensates and 'slow light'.