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Ménoret V Geiger R Stern G Zahzam N Battelier B Bresson A Landragin A Bouyer P 《Optics letters》2011,36(21):4128-4130
We present a compact and stable dual-wavelength laser source for onboard atom interferometry with two different atomic species. It is based on frequency-doubled telecom lasers locked on a femtosecond optical frequency comb. We take advantage of the maturity of fiber telecom technology to reduce the number of free-space optical components, which are intrinsically less stable, and to make the setup immune to vibrations and thermal fluctuations. The source provides the frequency agility and phase stability required for atom interferometry and can easily be adapted to other cold atom experiments. We have shown its robustness by achieving the first dual-species K-Rb magneto-optical trap in microgravity during parabolic flights. 相似文献
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Coupling by the resonant dipole-dipole energy transfer between cold cesium Rydberg atoms is investigated using time-resolved narrow-band deexcitation spectroscopy. This technique combines the advantage of efficient Rydberg excitation with high-resolution spectroscopy at variable interaction times. Dipole-dipole interaction is observed spectroscopically as avoided level crossing. The coherent character of the process is linked to back and forth transfer in the np + np <--> ns + (n + 1)s reaction. Decoherence in the ensemble has two different origins: the atom motion induced by dipole-dipole interaction and the migration of the s-Rydberg excitation in the environment of p-Rydberg atoms. 相似文献
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O. Carraz F. Lienhart R. Charrière M. Cadoret N. Zahzam Y. Bidel A. Bresson 《Applied physics. B, Lasers and optics》2009,97(2):405-411
We propose a compact and robust laser system at 780 nm for onboard atomic inertial sensors based on rubidium atom interferometry.
The principle of this system consists in doubling the frequency of a telecom fiber bench at 1560 nm. The same laser source
is used to achieve a magneto-optical trap, matter–wave interferences, and the atomic detection. An atomic gravimeter has been
realized and the laser system has been validated under hyper- and microgravity. 相似文献
4.
G. Stern B. Battelier R. Geiger G. Varoquaux A. Villing F. Moron O. Carraz N. Zahzam Y. Bidel W. Chaibi F. Pereira Dos Santos A. Bresson A. Landragin P. Bouyer 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2009,53(3):353-357
We describe the operation of a light pulse interferometer using cold 87Rb atoms in reduced gravity. Using a series of two Raman transitions induced by light pulses, we have obtained Ramsey fringes
in the low gravity environment achieved during parabolic flights. With our compact apparatus, we have operated in a regime
which is not accessible on ground. In the much lower gravity environment and lower vibration level of a satellite, our cold
atom interferometer could measure accelerations with a sensitivity orders of magnitude better than the best ground based accelerometers
and close to proven spaced-based ones. 相似文献
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T. Pohl D. Comparat N. Zahzam T. Vogt P. Pillet T. Pattard 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2006,40(1):45-50
We investigate the idea of adding Rydberg
atoms to an ultracold plasma to control the electronic
temperature of the plasma. We show that a certain amount of control is indeed
possible, and discuss limitations for the extent of electron cooling.
Experimental data are found to be in good agreement with numerical simulations. 相似文献
7.
N.?Hoang N.?Zahzam S.?GuibalEmail author P.?Pillet 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2005,36(1):95-100
A new scheme for trapping Cs atoms in a non dissipative trap has been developed. The trap involves both optical dipole forces
and magnetic forces. This device is suitable for Cs atoms in the lowest energy Zeeman sublevel, thus avoiding the two-body
inelastic collisions which prevented reaching Bose-Einstein condensation of Cs in purely magnetic traps. Furthermore, an additional
magnetic field can be applied, allowing a fine tuning of the two-body elastic collision cross-section. We report on the experimental
realization of such a trap and describe the characteristics of the trapped atomic sample. An analysis of the collisional regime
is performed using measurements of the damping of the oscillatory modes of the trapped atom cloud. 相似文献
8.
F. Lienhart S. Boussen O. Carraz N. Zahzam Y. Bidel A. Bresson 《Applied physics. B, Lasers and optics》2007,89(2-3):177-180
We propose a new compact and reliable laser system for rubidium laser cooling in onboard experiments like atomic clocks or
atomic inertial sensors. The system is based on the frequency doubling of a telecom fiber bench at 1560 nm. Fiber components
at 1560 nm allow us to generate the repumping laser and to control dynamically the power and the frequency of the 780 nm laser.
With this laser system, we obtain a magneto-optical trap of 85Rb even in the presence of mechanical vibrations and strong thermal variations (12 °C in 30 min).
PACS 32.80.Pj; 42.60.-v; 42.81.Wg; 42.65.Ky; 39.20.+q 相似文献
9.
Boussen S. Hoang N. Guibal S. Zahzam N. Pruvost L. Marescaux D. Pinard J. Pillet P. 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2004,28(2):259-266
Bose-Einstein condensation (BEC) in a atomic cesium gas prepared in a low field seeker Zeeman sublevel and confined in a magnetic trap has been thwarted by a high cross-section of inelastic spin-flip collisions. A recent experiment [1] succeeded in reaching BEC for cesium atoms using all optical methods and tuning the scattering length. We will discuss a hybrid magnetic and optical trap for cesium atoms in the true hyperfine ground state, the high field seeker Zeeman sublevel, F = m
F
= 3. Although this trap allows only one-dimensional (1D) evaporative cooling, we show that a route towards BEC with such a trap should be possible. We present simulations of 1D evaporative cooling, which shows that a high phase space density (PSD) of 0.1 could be reached in less than 10 seconds.Received: 25 July 2003PACS:
03.75.Hh Static properties of condensates; thermodynamical, statistical and structural properties - 05.30.Jp Boson systems - 32.80.Pj Optical cooling of atoms; trappingLaboratoire Aimé Cotton is associated with University of Paris-Sud. 相似文献
10.
Cold inelastic collisions between confined cesium (Cs) atoms and Cs2 molecules are investigated inside a CO2 laser dipole trap. Inelastic atom-molecule collisions can be observed and measured with a rate coefficient of approximately 2.6 x 10(-11) cm3 s(-1), mainly independent of the molecular rovibrational state populated. Lifetimes of purely atomic and molecular samples are essentially limited by rest gas collisions. The pure molecular trap lifetime ranges 0.3-1 s, 4 times smaller than the atomic one, as is also observed in a pure magnetic trap. We give an estimation of the inelastic molecule-molecule collision rate to be approximately 10(-11) cm3 s(-1). 相似文献
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