Many-body wave function for a quantum dot in a weak magnetic field

The ground states of parabolically confined electrons in a quantum dot are studied by both direct numerical diagonalization and quantum Monte Carlo (P MC) methods. We present a simple but accurate variational many-body wave fu nction for the dot in the limit of a weak magnetic field. The wave function has the center-of-mass motion restricted to the lowest-energy state and th e electron-electron interaction is taken into account by a Jastrow two-body correlation factor, The optimized wave function has an accuracy very close to the state-of-the-art numerical diagonalization calculations. The result s and the computational efficiency indicate that the presented wave functio n combined with the QMC method suits ideally for studies of large quantum d ots. [S0163-1829(99)07907-2].