Magnetic moment invariant Gaussian states of a charged particle in a homogeneous magnetic field
Institute of Physics, University of Brasilia, P.O. Box 04455, 70919-970, Brasilia, DF, Brazil
2 International Center for Physics, University of Brasilia, Brasilia, Brazil
Accepted: 4 May 2022
Published online: 12 May 2022
A two-parameter family of quantum states preserving the mean value of the magnetic moment (proportional to the kinetic angular momentum) is found for a charged particle in a constant homogeneous magnetic field in the presence of an isotropic two-dimensional parabolic potential, which can be either attractive or repulsive (the case of the Penning trap). The evolution of such states in a specific time-dependent magnetic field of the Epstein–Eckart form is studied, with an emphasis on the limit cases of the sudden jump and adiabatic approximations. The behavior in the case of magnetic field inversion is shown to be qualitatively different from the case when the field does not change its sign. The case of time-dependent vector potentials with a constant magnetic field (arising due to deformations of the shape of a solenoid) is considered, as well.
© The Author(s), under exclusive licence to Società Italiana di Fisica and Springer-Verlag GmbH Germany, part of Springer Nature 2022