En col·laboració amb la Universitat de Barcelona (UB), la Universitat Autònoma de Barcelona (UAB)i l’Institut de Ciències Fotòniques (ICFO)

We have studied how the ground state and the one-body density distribution of a one-dimensional system of bosons trapped by a harmonic oscillator potential depend on the repulsive interaction between the bosons. This study has been done using two numerical methods: Variational Monte Carlo and Diffusion Monte Carlo to retrieve information about the ground state energy and the one-body density distribution. We have covered the full range of interaction from the non-interacting regime, where the mean field approximation is a suitable way to describe our system, to the strongly interacting regime where we have reproduced approximately the behavior of a Tonks-Girardeau gas. As the repulsive interaction strength is increased, the system builds pair correlations. We have also proposed a correlated wave function to characterise these correlations.