Quantum dynamics of a charged particle in a penning trap

With the help of the exact classical path representation of the time dependent propagator the dynamics of a charged particle in a Penning trap in the presence of an additional classical, time-dependent electric field is investigated. In this way the connection between quantum and classical dynamics is exhibited in a clear way. The possibility of localizing a particle in the ground state of a Penning trap with unit probability by a suitably chosen electric field is discussed.