Relativistic and nonrelativistic models in one dimension which simulate the deuteron and the
3S1 nucleon-nucleon (NN) scattering are constructed and the relation between the scattering length
at and the root-mean-square radius
rm of the simulated deuteron is examined for a variety of interactions. The linear relation between
at and
rm, which was found by Klarsfeld et al. for realistic NN potentials, holds for a wide class of potentials, relativistic as well as nonrelativistic. Within the limitation of our one-dimensional models, this suggests that the discrepancy between theory and experiment which was pointed out by Klarsfeld et al. regarding
at and
rm cannot be resolved by relativistic effects.
The bound-state energy of a one-dimensional hydrogen atom with a δ-function potential is modified by the presence of a nearby boundary. The distortion of the wave function raises the energy of the atom. If the atom is sufficiently close to a high barrier the system does not have a bound state. Scattering from a δ-function potential is also modified by the presence of the boundary. This simple example, which can be solved exactly, may help to provide insight into more realistic interactions between single atoms and surfaces.
We propose a configuration of a magnetic microtrap that can be used as an interferometer for three-dimensionally trapped atoms. The interferometer is realized via a dynamic splitting potential that transforms from a single well into two separate wells and back. The ports of the interferometer are neighboring vibrational states in the single-well potential. We present a one-dimensional model of this interferometer and compute the probability of unwanted vibrational excitations for a realistic magnetic potential. We optimize the speed of the splitting process in order to suppress these excitations, and conclude that such interferometer device should be feasible with currently available microtrap technique.