Orbital magnetic properties of quantum dots: the role of electron-electron interactions

We study the magnetic orbital response of a system of N interacting electrons confined in a two-dimensional geometry and subjected to a perpendicular magnetic field in the finite temperature Hartree-Fock approximation. The electron-electron interaction is modelled by a short-range Yukawa-type potential. We calculate the ground state energy, magnetization, and magnetic susceptibility as a function of the temperature, the potential range, and the magnetic field. We show that the amplitude and period of oscillations in the magnetic susceptibility are strongly affected by the electron-electron interaction as evidenced in experimental results. The zero-field susceptibility displays both paramagnetic and diamagnetic phases as a function of temperature and the number of confined electrons.