Landau states in time-dependent magnetic fields

Abstract

We present the oscillator representation of the Pauli Hamiltonian for a scalar charge in a magnetic field and find a basis that diagonalizes the Hamiltonian in the special case of a constant or slowly varying magnetic field. We show that the diagonalization of the new basis is a canonical transformation in phase space, which leads to the Pauli Hamiltonian and counts the degeneracy of the Landau levels. Finally, we obtain the Liouville-von Neumann equation for quantum invariants as the annihilation and the creation operators for a scalar charge in time-dependent magnetic fields.