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Laser Coolingl Trapping and Control of Atoms
Published in Yu. N. Kulchin, Modern Optics and Photonics of Nano and Microsystems, 2018
Atomic optics is the optics of material particles and deals with the problems of formation of ensembles and beams of neutral atoms, their control, and also questions of their application. Atomic optics was formed into an independent discipline in the mid‐1980s as a result of studies of the effect of laser radiation pressure on the translational motion of atoms.
Construction and characterization of a continuous atom beam interferometer
Published in Journal of Modern Optics, 2020
M. P. Manicchia, J. Lee, G. R. Welch, J. Mimih, F. A. Narducci
In this paper, we begin theoretical and experimental exploration of a system that addresses these problems. Instead of clouds of cold atoms launched from a trap, we use atoms that continually emerge from a 2-dimensional magneto-optical trap (2D-MOT). The atoms pass through continuous laser beams that form the atom optics. The transit times of the atoms through the laser beams form the laser ‘pulses.’ This approach removes the problems of pulsed operation described above. However, this approach does require additional considerations that the pulsed scheme does not. The atoms have a velocity spread, and so not all the atoms see the same ‘pulse time.’ This effect was considered in a previous publication (7). Additionally, the unavoidable effects of laser and atomic beam divergence can degrade the interference pattern. In this paper, we consider the effects of velocity averaging, as well as laser and atom beam divergence on this system. Such effects have been considered in prior publications, e.g. (4), but in different operating regimes. Similar systems have also been demonstrated before but using microwave cavities (8) and using atoms extracted from a low-velocity intense source (LVIS) (9).
Matter-wave interferometry with atoms in high Rydberg states
Published in Molecular Physics, 2019
In all Rydberg-Stark deceleration experiments up to now, the atoms or molecules were prepared in selected Rydberg states by laser photoexcitation, and, under the conditions in which the experiments were performed, quantisation of the motional states of the samples could be neglected. Consequently, this set of methodologies can be classified as incoherent Rydberg atom or molecule optics. Here we present the results of Rydberg-Stark deceleration experiments performed with atoms prepared in coherent superpositions of Rydberg states with different electric dipole moments. In the presence of inhomogeneous electric fields the different forces on these internal state components allow the generation of superpositions of momentum states which have been exploited for Rydberg-atom interferometry. Experiments of the kind reported here may be classified as coherent Rydberg atom optics. The results presented open new opportunities in the exploration of the boundary between quantum and classical mechanics, the study of spatial decoherence in large quantum systems [29], and measurements of the acceleration of neutral particles composed of antimatter, e.g. Rydberg positronium or antihydrogen, in the gravitational field of the Earth [30–33].
Focusing properties and focal shift of partially coherent vortex cosine-hyperbolic-Gaussian beams
Published in Journal of Modern Optics, 2022
Z. Hricha, E. M. El Halba, M. Lazrek, A. Belafhal
In summary, we have investigated the focusing properties of a PCvChGB passing through a thin lens system. The analytical expression of the intensity distribution of a PCvChGB is derived within the framework of coherence theory and by using the extended Collins formula. Numerical illustrative examples have been presented to discuss the effects of the coherence length, the beam parameters, and the Fresnel number on the evolution of the intensity distribution and the focal shift behaviour of the focused PCvChGB. It is shown that the intensity pattern and focal shift can be controlled by changing the beam parameters conditions. The obtained results could be beneficial for applications of PCvChBs in beam shaping, optical communications, and atom optics.