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In this paper, we report our progress towards the realization of a continuous guided atomic beam in the degenerate regime. So far, we have coupled into a magnetic guide a flux of a few $10^{8}$ atoms/s at 60 cm/s with a propagation in the guide over more than 2 meters. At this stage, the collision rate is not high enough to start an efficient forced evaporative cooling. Here we describe a new approach to reach the collisional regime. It is based on a pulsed feeding of the magnetic guide at a high repetition rate. The overlap of the packets of atoms occurs in the guide and leads to a continuous guided beam. We discuss different ways to increase the collision rate of this beam while keeping the phase space density constant by shaping the external potential.
We describe the realization of a magnetically guided beam of cold rubidium atoms, with a flux of $7times 10^9$ atoms/s, a temperature of 400 $mu$K and a mean velocity of 1 m/s. The rate of elastic collisions within the beam is sufficient to ensure th
We report on our recent progress in the manipulation and cooling of a magnetically guided, high flux beam of $^{87}{rm Rb}$ atoms. Typically $7times 10^9$ atoms per second propagate in a magnetic guide providing a transverse gradient of 800 G/cm, wit
In this work we report on a detailed analysis of the propagation of high energy electron beams having different shapes in a model system, namely [100] oriented zincblende GaN crystal. The analyses are based on the comparison between a reformulated Bl
We address the question of how participants in a small world experiment are able to find short paths in a social network using only local information about their immediate contacts. We simulate such experiments on a network of actual email contacts w
We decipher the microscopic mechanism of the formation of tilt in the two-dimensional Dirac cone of $8Pmmn$ borophene sheet. With the aid of $ab~ initio$ calculations, we identify relevant low-energy degrees of freedom on the $8Pmmn$ lattice and find