851 citations · 2.7k across the 59 of their papers we have counts for
16 papers · 1 filter
Phase space density limitation in laser cooling without spontaneous emission
Thierry Chanelière, Daniel Comparat, Hans Lignier
We study the possibility to enhance the phase space density of non-interacting particles submitted to a classical laser field without spontaneous emission. We clearly state that, w…
Bichromatic magneto-optical trapping for configurations
Anne Cournol, Pierre Pillet, Hans Lignier +1
A magneto-optical trap (MOT) of atoms or molecules is studied when two lasers of different detunings and polarization are used. Especially for transitions, a s…
Coherent excitation of a single atom to a Rydberg state
Y. Miroshnychenko, A. Gaëtan, C. Evellin +5
We present the coherent excitation of a single Rubidium atom to the Rydberg state (58d3/2) using a two-photon transition. The experimental setup is described in detail, as well as…
General conditions for a quantum adiabatic evolution
Daniel Comparat
Adiabaticity occurs when, during its evolution, a physical system remains in the instantaneous eigenstate of the hamiltonian. Unfortunately, existing results, such as the quantum a…
Observation of collective excitation of two individual atoms in the Rydberg blockade regime
A. Gaëtan, Y. Miroshnychenko, T. Wilk +6
The dipole blockade between Rydberg atoms has been proposed as a basic tool in quantum information processing with neutral atoms. Here we demonstrate experimentally the Rydberg blo…
Efficient positronium laser excitation for antihydrogen production in a magnetic field
F. Castelli, I. Boscolo, S. Cialdi +2
Antihydrogen production by charge exchange reaction between Positronium (Ps) atoms and antiprotons requires an efficient excitation of Ps atoms up to high-n levels (Rydberg levels)…
General conditions for a quantum adiabatic evolution
Daniel Comparat
The smallness of the variation rate of the hamiltonian matrix elements compared to the (square of the) energy spectrum gap is usually believed to be the key parameter for a quantum…
Optimized production of large Bose Einstein Condensates
D. Comparat, A. Fioretti, G. Stern +3
We suggest different simple schemes to efficiently load and evaporate a ''dimple'' crossed dipolar trap. The collisional processes between atoms which are trapped in a reservoir lo…
Non-Holonomic Control IV : Coherence Protection in a Rubidium isotope
E. Brion, V. M. Akulin, D. Comparat +6
In this paper, we present a realistic application of the coherence protection method proposed in the previous article. A qubit of information encoded on the two spin states of a Ru…
Non-Holonomic Control III : Coherence Protection by the Quantum Zeno Effect and Non-Holonomic Control
E. Brion, V. M. Akulin, D. Comparat +6
In this paper, we present a coherence protection method based upon a multidimensional generalization of the Quantum Zeno Effect, as well as ideas from the coding theory. The non-ho…
Non-holonomic Control II : Non-holonomic Quantum Devices
E. Brion, V. M. Akulin, D. Comparat +6
In this paper, we show how the non-holonomic control technique can be employed to build completely controlled quantum devices. Examples of such controlled structures are provided.
Non-Holonomic Control I
E. Brion, V. M. Akulin, D. Comparat +6
In this paper, we present a universal control technique, the non-holonomic control, which allows us to impose any arbitrarily prescribed unitary evolution to any quantum system thr…
Implementation of a CNOT gate in two Rydberg atoms by the nonholonomic control technique
E. Brion, D. Comparat, G. Harel
We present a demonstrative application of the nonholonomic control method to a real physical system composed of two cold Cesium atoms. In particular, we show how to implement a CNO…
Coherence protection by the quantum Zeno effect and non-holonomic control in a Rydberg Rubidium isotope
E. Brion, V. M. Akulin, D. Comparat +6
The protection of the coherence of open quantum systems against the influence of their environment is a very topical issue. A scheme is proposed here which protects a general quant…
Ionization of Rydberg atoms embedded in an ultracold plasma
Nicolas Vanhaecke, Daniel Comparat, Duncan A. Tate +1
We have studied the behavior of cold Rydberg atoms embedded in an ultracold plasma. We demonstrate that even deeply bound Rydberg atoms are completely ionized in such an environmen…
Improved LeRoy-Bernstein near-dissociation expansion formula. Tutorial application to photoassociation spectroscopy of long-range states
Daniel Comparat
NDE (Near-dissociation expansion) including LeRoy-Bernstein formulas are improved by taking into account the multipole expansion coefficients and the non asymptotic part of the pot…