Wave-Packet Dynamics of Atoms in Optical Lattices

Raithel, Birkl, Phillips +1 more

Sergey V. Prants, Leonid E. Kon’kov

Thomas Lauber, Pietro Massignan, G. Birkl +1 more

Atomic wave packets in optical lattices which are both spatially finite and time dependent exhibit many striking similarities with light pulses in photonic crystals. We analytically characterize the transmission properties of such a potential geometry for an ideal gas in terms of a position-dependent band structure. In particular, we find that at specific energies, wave packets at the centre of the finite lattice may be enclosed by pairs of band gaps. These act as mirrors between which the atomic wave packet is reflected, thereby effectively yielding a matter wave cavity. We show that long trapping times may be obtained in such a resonator and investigate the collapse and revival dynamics of the atomic wave packet by numerical evaluation of the Schrödinger equation.

Poul L. Pedersen, Miroslav Gajdacz, N. Winter +3 more

Within the combined potential of an optical lattice and a harmonic magnetic trap, it is possible to form matter wave packets by intensity modulation of the lattice. An analysis of the production and motion of these wave packets provides a detailed understanding of the dynamical evolution of the system. The modulation technique also allows for a controllable transfer (deexcitation) of atoms from such wave packets to a state bound by the lattice. Thus, it acts as a beam splitter for matter waves that can selectively address different bands, enabling the preparation of atoms in localized states. The combination of wave packet creation and deexcitation closely resembles the well-known method of pump-probe spectroscopy. Here, we use the deexcitation for spectroscopy of the anharmonicity of the combined potential. Finally, we demonstrate that lattice modulation can be used to excite matter wave packets to even higher momenta, producing fast wave packets with potential applications in precision measurements.

Georg A. Raithel, G. Birkl, William D. Phillips +1 more

Victor Yu. Argonov, Sergey V. Prants