Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe

A: Fachverband Atomphysik

A 8: Poster I

A 8.23: Poster

Dienstag, 9. März 2010, 16:30–19:00, Lichthof

Quantum Walks and Single Atom Inteferometry with neutral atoms in a 1D lattice — •Noomen Belmechri, Michał Karski, Leonid Förster, Jai-Min Choi, Andreas Steffen, Wolfgang Alt, Dieter Meschede, and Artur Widera — Institut für Angewandte Physik der Universität Bonn Wegelerstraße 8, 53115 Bonn, Germany.

We present applications of state-dependent transport in a 1D optical lattice, in particular matter-wave interference starting from a single atom. Individual Cs atoms are trapped in a standing wave that is composed of two polarizations acting independently on the two qubit states. By displacing the sublattices, we coherently transport atoms across several µm and spatially split the wavefunction of superposition states. Repeated application of a π/2-pulse and a transport step realizes a quantum walk with up to 24 steps, allowing us to observe superclassical spreading of the walk as well as recombination to a single site by unitary reversal. Adding state-selective detection, a full state tomography could be performed. The decoherence sources limiting the walk have been investigated.

We also split and recombine an individual atomic wavefunction, reading out the phase difference. In the presence of a magnetic gradient, the phase accumulation incorporates the Zeeman shift difference, making the atom interferometer the basis for a local magnetic field probe. We report on our characterization of the phase evolution caused by the lattice shift operation and our results in a strong gradient.