Optical lattices are formed when cold atoms get trapped in the periodic array of optical potential wells created by a number of traveling light waves. Exact periodicity is guaranteed when the number of traveling waves exceeds the number of dimensions by no more than one. We present a few simple exactly solvable models for the transport of atoms over a lattice in the tight-binding limit. One model concerns the spreading of an atom by tunneling through the barriers and by momentum recoil induced by optical pumping. Another model gives results for the amplitude of Bloch oscillations, which occur when a uniform is added to the periodic potential. Finally the dissipative spreading of the quasimomentum due to optical pumping is modeled.Optical lattices are formed when cold atoms get trapped in the periodic array of optical potential wells created by a number of traveling light waves. Exact periodicity is guaranteed when the number of traveling waves exceeds the number of dimensions by no more than one. We present a few simple exactly solvable models for the transport of atoms over a lattice in the tight-binding limit. One model concerns the spreading of an atom by tunneling through the barriers and by momentum recoil induced by optical pumping. Another model gives results for the amplitude of Bloch oscillations, which occur when a uniform is added to the periodic potential. Finally the dissipative spreading of the quasimomentum due to optical pumping is modeled.

Physica ScriptaJan 1, 20012 citations

Synchronization of Hamiltonian motion and dissipative effects in optical lattices: Evidence for a stochastic resonance

Laurent Sanchez-Palencia, G. Grynberg

We theoretically study the influence of the noise strength on the excitation of the Brillouin propagation modes in a dissipative optical lattice. We show that the excitation has a resonant behavior for a specific amount of noise corresponding to the precise synchronization of the Hamiltonian motion on the optical potential surfaces and the dissipative effects associated to optical pumping in the lattice. This corresponds to the phenomenon of stochastic resonance. Our results are obtained by numerical simulations and correspond to the analysis of microscopic quantities (atomic spatial distributions) as well as macroscopic quantities (enhancement of spatial diffusion and pump-probe spectra). We also present a simple analytical model in excellent agreement with the simulations.We theoretically study the influence of the noise strength on the excitation of the Brillouin propagation modes in a dissipative optical lattice. We show that the excitation has a resonant behavior for a specific amount of noise corresponding to the precise synchronization of the Hamiltonian motion on the optical potential surfaces and the dissipative effects associated to optical pumping in the lattice. This corresponds to the phenomenon of stochastic resonance. Our results are obtained by numerical simulations and correspond to the analysis of microscopic quantities (atomic spatial distributions) as well as macroscopic quantities (enhancement of spatial diffusion and pump-probe spectra). We also present a simple analytical model in excellent agreement with the simulations.

arXiv:quant-ph/0309210Physical Review AAug 20, 20037 citations

Optical Lattices

WORLD SCIENTIFIC eBooksJul 1, 20100 citations

Combined quantum-state preparation and laser cooling of a continuous beam of cold atoms

Gianni Di Domenico, Laurent Devenoges, Claire Dumas +1 more

We use two-laser optical pumping on a continuous atomic fountain in order to prepare cold cesium atoms in the same quantum ground state. A first laser excites the $F=4$ ground state to pump the atoms toward $F=3$ while a second $\ensuremath{\pi}$-polarized laser excites the $F=3\ensuremath{\rightarrow}{F}^{'}=3$ transition of the ${D}_{2}$ line to produce Zeeman pumping toward $m=0$ . To avoid trap states, we implement the first laser in a two-dimensional optical lattice geometry, thereby creating polarization gradients. This configuration has the advantage of simultaneously producing Sisyphus cooling when the optical lattice laser is tuned between the $F=4\ensuremath{\rightarrow}{F}^{'}=4$ and $F=4\ensuremath{\rightarrow}{F}^{'}=5$ transitions of the ${D}_{2}$ line, which is important to remove the heat produced by optical pumping. Detuning the frequency of the second $\ensuremath{\pi}$-polarized laser reveals the action of a mechanism improving both laser cooling and state-preparation efficiency. A physical interpretation of this mechanism is discussed.We use two-laser optical pumping on a continuous atomic fountain in order to prepare cold cesium atoms in the same quantum ground state. A first laser excites the $F=4$ ground state to pump the atoms toward $F=3$ while a second $\ensuremath{\pi}$-polarized laser excites the $F=3\ensuremath{\rightarrow}{F}^{'}=3$ transition of the ${D}_{2}$ line to produce Zeeman pumping toward $m=0$. To avoid trap states, we implement the first laser in a two-dimensional optical lattice geometry, thereby creating polarization gradients. This configuration has the advantage of simultaneously producing Sisyphus cooling when the optical lattice laser is tuned between the $F=4\ensuremath{\rightarrow}{F}^{'}=4$ and $F=4\ensuremath{\rightarrow}{F}^{'}=5$ transitions of the ${D}_{2}$ line, which is important to remove the heat produced by optical pumping. Detuning the frequency of the second $\ensuremath{\pi}$-polarized laser reveals the action of a mechanism improving both laser cooling and state-preparation efficiency. A physical interpretation of this mechanism is discussed.

arXiv:1009.1358Physical Review ANov 29, 201020 citations

We use two-laser optical pumping on a continuous atomic fountain in order to prepare cold cesium atoms in the same quantum ground state. A first laser excites the

F=4

ground state to pump the atoms toward

F=3

while a second $\ensuremath{\pi}$-polarized laser excites the $F=3\ensuremath{\rightarrow}{F}^{'}=3$ transition of the

{D}_{2}

line to produce Zeeman pumping toward

m=0

. To avoid trap states, we implement the first laser in a two-dimensional optical lattice geometry, thereby creating polarization gradients. This configuration has the advantage of simultaneously producing Sisyphus cooling when the optical lattice laser is tuned between the $F=4\ensuremath{\rightarrow}{F}^{'}=4$ and $F=4\ensuremath{\rightarrow}{F}^{'}=5$ transitions of the

{D}_{2}

line, which is important to remove the heat produced by optical pumping. Detuning the frequency of the second $\ensuremath{\pi}$-polarized laser reveals the action of a mechanism improving both laser cooling and state-preparation efficiency. A physical interpretation of this mechanism is discussed.