Coherent transport of cold atoms in angle-tuned optical lattices

We examine the dynamics of ultracold atoms held in optical lattice potentials. By controlling the switching of a periodic driving potential we show how a phase-induced renormalization of the intersite tunneling can be used to produce directed motion and control wavepacket spreading. We further show how this generation of a synthetic gauge potential can be used to split and recombine wavepackets, providing an attractive route to implementing quantum computing tasks.

We report on the transport of ultracold cesium and rubidium atoms over $37.2\,$cm in under $25\,$ms using an optical conveyor belt formed by two counter-propagating beams with a controllable frequency difference that generate a movable optical lattice. By carefully selecting the waists and focus positions, we are able to use two static Gaussian beams for the transport, avoiding the need for a Bessel beam or vari-focus lenses. We characterize the transport efficiency for both ...

We report on three-dimensional optical trapping of single ions in an optical lattice formed by two counter-propagating laser beams. We characterize the trapping parameters of the standing wave using the ion as a sensor stored in a hybrid trap consisting of a radio-frequency (rf), a dc, and the optical potential. When loading ions directly from the rf into the standing-wave trap, we observe a dominant heating rate. Monte Carlo simulations confirm rf-induced parametric excitati...

We describe an atom trapping mechanism based upon differential optical pumping between metastable hyperfine states by partially-displaced laser beams in the absence of a magnetic field. With realistic laser powers, trap spring constants should match or exceed those typical of magneto-optical traps, and highly flexible tailored trap shapes should be achievable. In a proof-of-principle experiment, we have combined a 1D implementation with magneto-optical trapping in the orthogo...

For ultracold and Bose-condensed atoms contained in periodic optical potential wells the quantized nature of their motion is clearly visible. The motion of the atomic wavepacket can also be accurately controlled. For those systems the long-range character of the atomic interaction and of the external potential play a key role in the quantum mechanical evolution. The basic facets of the experimental and theoretical research for atoms within optical lattice structures will be r...

We provide an analytical description of the dynamics of an atom in an optical lattice using the method of perturbative adiabatic expansion. A precise understanding of the lattice-atom interaction is essential to taking full advantage of the promising applications that optical lattices offer in the field of atom interferometry. One such application is the implementation of Large Momentum Transfer (LMT) beam splitters that can potentially provide multiple order of magnitude inc...

We implement and demonstrate the effectiveness of a cooling scheme using a moving, all-optical, one-way barrier to cool a sample of $^{87}$Rb atoms, achieving nearly a factor of 2 reduction in temperature. The one-way barrier, composed of two focused, Gaussian laser beams, allows atoms incident on one side to transmit, while reflecting atoms incident on the other. The one-way barrier is adiabatically swept through a sample of atoms contained in a far-off-resonant, single-beam...

We present a very simple model for realizing directed transport with cold atoms in a pair of periodically flashed optical lattices. The origin of this ratchet effect is explained and its robustness demonstrated under imperfections typical of cold atom experiments. We conclude that our model offers a clear-cut way to implement directed transport in an atom optical experiment.

We control the quantum mechanical motion of neutral atoms in an optical lattice by driving microwave transitions between spin states whose trapping potentials are spatially offset. Control of this offset with nanometer precision allows for adjustment of the coupling strength between different motional states, analogous to an adjustable effective Lamb-Dicke factor. This is used both for efficient one-dimensional sideband cooling of individual atoms to a vibrational ground stat...

We show the possibility of implementing a deep dissipative optical lattice for neutral atoms with a macroscopic period. The depth of the lattice can reach magnitudes comparable to the depth of the magneto-optical traps (MOT), while the presence of dissipative friction forces allows for trapping and cooling of atoms. The area of localization of trapped atoms reaches sub-millimeter size, and the number of atoms is comparable to the number trapped in MOT. As an example, we study...