Bachelor defence by Martin Asbjørn Krehbiel

Modelling the quantum spin noise of moving atoms

The study of the spin noise spectrum of hot gas-cells is important to science and have a diverse range of applications. However these systems are hard to model using analytical tools. This is in no small part due to the many effects included in such a system most importantly the motion of the atoms. As an attempted remedy a script for modelling these systems numerically was developed. The script simulates atoms as point-particles susceptible to Brownian motion and obey Knudsen’s cosine law in the case of a collision with the walls of the cell. The spins of the atoms are subject to Stark shifts, magnetic inhomogeneity and inhomogeneous light atom coupling. The script does not take into account higher order terms or back action. The script was successful at showing key features of the spin noise spectrum.