85 research outputs found
Coherent Control of Dressed Matter Waves
No full textWe demonstrate experimentally that matter waves can be coherently and adiabatically loaded and controlled in one-, two-, and three-dimensional strongly driven optical lattices. This coherent control is then used in order to reversibly induce the superfluid-Mott insulator phase transition by changing the strength of the driving. Our findings pave the way for studies of driven quantum systems and new methods for controlling matter waves
Henri Romagnesi. — Nouvel Atlas des Champignons. Tome III, 82 pl. couleurs par A. Bride, J. Chenantais, H. Essettte, J.-L. Lemoine, Lignier, G. Malençon, F. Margaine et H. Romagnesi, Paris, 1961
No full textHenri Romagnesi. — Nouvel Atlas des Champignons. Tome III, 82 pl. couleurs par A. Bride, J. Chenantais, H. Essettte, J.-L. Lemoine, Lignier, G. Malençon, F. Margaine et H. Romagnesi, Paris, 1961. In: Bulletin mensuel de la Société linnéenne de Lyon, 31ᵉ année, n°4, avril 1962. p. 127
Henri Romagnesi. — Nouvel Atlas des Champignons. Tome III, 82 pl. couleurs par A. Bride, J. Chenantais, H. Essettte, J.-L. Lemoine, Lignier, G. Malençon, F. Margaine et H. Romagnesi, Paris, 1961
No full textHenri Romagnesi. — Nouvel Atlas des Champignons. Tome III, 82 pl. couleurs par A. Bride, J. Chenantais, H. Essettte, J.-L. Lemoine, Lignier, G. Malençon, F. Margaine et H. Romagnesi, Paris, 1961. In: Bulletin mensuel de la Société linnéenne de Lyon, 31ᵉ année, n°4, avril 1962. p. 127
Tunneling control and localization for Bose-Einstein condensates in a frequency modulated optical lattice
No full textThe similarity between matter waves in periodic potential and solid-state
physics processes has triggered the interest in quantum simulation using
Bose-Fermi ultracold gases in optical lattices. The present work evidences the
similarity between electrons moving under the application of oscillating
electromagnetic fields and matter waves experiencing an optical lattice
modulated by a frequency difference, equivalent to a spatially shaken periodic
potential. We demonstrate that the tunneling properties of a Bose-Einstein
condensate in shaken periodic potentials can be precisely controlled. We take
additional crucial steps towards future applications of this method by proving
that the strong shaking of the optical lattice preserves the coherence of the
matter wavefunction and that the shaking parameters can be changed
adiabatically, even in the presence of interactions. We induce reversibly the
quantum phase transition to the Mott insulator in a driven periodic potential
The microwave Stark and Fourier transform spectra, structure and quadrupole coupling constants of 1,2-dicyanocyclobutene
No full textThe microwave spectrum of 1,2-dicyanocyclobutene, C4H4(CN)(2), has been investigated using a Stark microwave spectrometer in the 11.0-34.0 GHz spectral region, and a Fourier transform microwave spectrometer in the 6-18 GHz region. The ground and several vibrationally excited states of the parent species have been assigned, as have the ground state of several C-13 and N-15 isotopomers. The nuclear quadrupole coupling constants of the N-14 nucleus have been determined for several species. The effective (r(0)) structure of the molecule has been derived. The substitution (r(s)) structure of the heavy atoms has also been calculated. An anomalously short carbon-carbon double bond of 132.6(2) pm was found by the substitution method. This short bond length is shown to be unreliable. Advanced quantum chemical calculations have been carried out for the title compound as well as for the cyclobutene prototype. An accurate estimate of the equilibrium (r(c)) structures of cyclobutene as well as of 1,2-dicyanocyclobutene based on quantum chemical calculations has been made. (C) 2002 Elsevier Science B.V. All rights reserved
The microwave Stark and Fourier transform spectra, structure and quadrupole coupling constants of 1,2-dicyanocyclobutene (vol 615, pg 315, 2002)
No full textRovibrational cooling of molecules by optical pumping
No full textSUMMARY We demonstrate rotational and vibrational cooling of cesium dimers by optical
pumping techniques. We use two laser sources exciting all the populated
rovibrational states, except a target state that thus behaves like a dark state
where molecules pile up thanks to absorption-spontaneous emission cycles. We
are able to accumulate photoassociated cold Cs2 molecules in their absolute
ground state (v = 0, J = 0) with up to 40% efficiency. Given its simplicity,
the method could be extended to other molecules and molecular beams. It also
opens up general perspectives in laser cooling the external degrees of freedom
of molecules
Resonantly enhanced tunneling of Bose-Einstein condensates in periodic potentials
No full textWe report on measurements of resonantly enhanced tunneling of Bose-Einstein condensates loaded into an optical lattice. By controlling the initial conditions of our system we were able to observe resonant tunneling in the ground and the first two excited states of the lattice wells. We also investigated the effect of the intrinsic nonlinearity of the condensate on the tunneling resonances
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