Seminarium Optyczne

Experiments with the Bose-Einstein condensates performed in the recent years prove that it is now possible to measure equilibrium statistical quantities that were more challenging than the average number of atoms in the condensate. In particular, fluctuations of the condensate occupation have been observed for the first time [M.Kristensen, et al. PRL 122, 163601 (2019)]. In this context, we present broad theoretical analysis of statistical properties of cold Bose gas confined to a ring trap. In my talk I will discuss methods that we use to deal with interacting system and present results concerning fluctuations and several other macroscopic state functions calculated for interacting and ideal gas of bosons.