Showing papers by "Stéphane Guérin published in 2010"
TL;DR: In this article, a generalized adiabatic approximation for a two-state dissipative Hamiltonian is presented, which is valid beyond weak dissipation regimes, using the formalism of Stokes lines.
Abstract: A generalized adiabatic approximation is formulated for a two-state dissipative Hamiltonian which is valid beyond weak dissipation regimes. The history of the adiabatic passage is described by superadiabatic bases as in the nondissipative regime. The topology of the eigenvalue surfaces shows that the population transfer requires, in general, a strong coupling with respect to the dissipation rate. We present, furthermore, an extension of the Davis-Dykhne-Pechukas formula to the dissipative regime using the formalism of Stokes lines. Processes of population transfer by an external frequency-chirped pulse-shaped field are given as examples.
27 citations
TL;DR: In this paper, the authors demonstrate the ultrafast coherent control of a nonlinear two-photon absorption in a dynamically shifted energy level structure using a spectrotemporal laser-pulse shaping that is programed to preserve the resonant absorption condition during the intense laser field interaction.
Abstract: We demonstrate the ultrafast coherent control of a nonlinear two-photon absorption in a dynamically shifted energy level structure. We use a spectrotemporal laser-pulse shaping that is programed to preserve the resonant absorption condition during the intense laser-field interaction. Experiments carried out in the strong-field regime of two-photon absorption in the ground state of atomic cesium reveal that the analytically obtained offset and curvature of a laser spectrum compensate the effect of both static and dynamic energy shifts of the given light-atom interaction.
14 citations
TL;DR: In this paper, the authors proposed two relatively robust schemes to generate controllable (deterministic) atomic W states of three Λ-like atoms interacting with an optical cavity and a laser beam.
13 citations
TL;DR: In this paper, the same cavity-mode photons are emitted from the cavity with near-unit efficiency in well-defined temporal modes of identical shapes controlled by the laser fields, and the second-order correlation function reveals the single-photon nature of the proposed source.
Abstract: We present a mechanism to produce indistinguishable single-photon pulses on demand from an optical cavity. The sequences of two laser pulses generate, at the two Raman transitions of a four-level atom, the same cavity-mode photons without repumping of the atom between photon generations. Photons are emitted from the cavity with near-unit efficiency in well-defined temporal modes of identical shapes controlled by the laser fields. The second-order correlation function reveals the single-photon nature of the proposed source. A realistic setup for the experimental implementation is presented.
13 citations
TL;DR: In this paper, a train of ultrashort laser pulses combined with weak control fields is used to suppress a transition while simultaneously enhancing the desired transitions, which can be used to produce a superposition of atomic and molecular states.
Abstract: We propose a mechanism to produce a superposition of atomic and molecular states by a train of ultrashort laser pulses combined with weak control fields By adjusting the repetition rate of the pump pulses and the intensity of the coupling laser, one can suppress a transition while simultaneously enhancing the desired transitions As an example, various superpositions of vibrational states of the K{sub 2} molecule are shown
6 citations