SearcharxivSearch

arXiv subjects

H. F. da Silva

Publications and source records attributed to H. F. da Silva.

2 recordsLinked to original sources

Progress towards a matter wave interferometer for inertial sensing with non-destructive monitoring of Bloch oscillations

We report on our progress in the construction of a continuous matter-wave interferometer for inertial sensing via the non-destructive observation of Bloch oscillations. At the present stage of the experiment, around $10^5$strontium-88 atoms are cooled down to below 1$μ$μK. Pumped by lasers red-tuned with respect to the 7.6 kHz broad intercombination transition of strontium, the two counterpropagating modes of the ring cavity form a one-dimensional optical lattice in which the atoms, accelerated by gravity, will perform Bloch oscillations. The atomic motion can be monitored in real-time via its impact on the counterpropagating light fields. We present the actual state of the experiment and characterize the laser spectrometer developed to drive the atom-cavity interaction.

physics.atom-ph

Transition from Knudsen to molecular diffusion in activity of absorbing irregular interfaces

We investigate through molecular dynamics the transition from Knudsen to molecular diffusion transport towards 2d absorbing interfaces with irregular geometry. Our results indicate that the length of the active zone decreases continuously with density from the Knudsen to the molecular diffusion regime. In the limit where molecular diffusion dominates, we find that this length approaches a constant value of the order of the system size, in agreement with theoretical predictions for Laplacian transport in irregular geometries. Finally, we show that all these features can be qualitatively described in terms of a simple random-walk model of the diffusion process.

cond-mat.dis-nn