Intertwining Operators Associated to a Family of Differential-Reflection Operators

Mediterranean Journal of Mathematics - We introduce a family of differential-reflection operators $${\Lambda_{A, \varepsilon}}$$ acting on smooth functions defined on $${{\mathbb R}}$$ . Here, A is...     

Compact and robust laser system for rubidium laser cooling based on the frequency doubling of a fiber bench at 1560 nm

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     

I.C.E.: a transportable atomic inertial sensor for test in microgravity

We present the construction of an atom interferometer for inertial sensing in microgravity, as part of the I.C.E. (Interférométrie Cohérente pour l’Espace) collaboration. On-board laser systems have been developed based on fibre-optic components, which are insensitive to mechanical vibrations and acoustic noise, have sub-MHz line width, and remain frequency stabilised for weeks at a time. A compact, transportable vacuum system has been built, and used for laser cooling and magneto-optical trapping. We will use a mixture of quantum degenerate gases, bosonic ⁸⁷Rb and fermionic ⁴⁰K, in order to find the optimal conditions for precision and sensitivity of inertial measurements. Microgravity will be realised in parabolic flights lasting up to 20 s in an Airbus. We investigate the experimental limits of our apparatus, and show that the factors limiting the sensitivity of a long-interrogation-time atomic inertial sensor are the phase noise in reference-frequency generation for Raman-pulse atomic beam splitters and acceleration fluctuations during free fall. PACS 06.30.Gv; 39.20.+q; 42.60.By     

Prospect for BEC in a cesium gas: one-dimensional evaporative cooling in a hybrid magnetic and optical trap

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.