Eur. Phys. J. D 35, 31-42 (2005)
https://doi.org/10.1140/epjd/e2005-00062-4

Selected aspects of the quantum dynamics and electronic structure of atoms in magnetic microtraps

¹ Physikalisches Institut, Universität Heidelberg, Philosophenweg 12, 69120 Heidelberg, Germany
² Theoretische Chemie, Institut für Physikalische Chemie, Universität Heidelberg, INF 229, 69120 Heidelberg, Germany

Corresponding authors: ^a ilesanov@physi.uni-heidelberg.de - ^b Peter.Schmelcher@pci.uni-heidelberg.de

Received: 4 February 2005
Revised: 18 March 2005
Published online: 3 May 2005

Abstract

We analyze the quantum properties of atoms in a magnetic quadrupole field. The quantum dynamics of ground state atoms in this field configuration is studied firstly. We formulate the Hamiltonian and perform a symmetry analysis. Due to the particular shape of the quadrupole field in general there exist no stable states. We provide resonance energies, lifetimes and calculate the density of states and investigate under what conditions quasi-bound states occur that possess long lifetimes. An effective scalar Schrödinger equation describing such states is derived. As a next step we explore the influence of a high gradient quadrupole field on the electronic structure of excited atoms. An effective one-body approach together with the fixed nucleus approximation is employed in order to derive the electronic Hamiltonian. We present the energy spectrum and discuss peculiar features such as non-trivial spin densities and magnetic field induced electric dipole moments.