We present experimental and theoretical studies of polarization-gradient cooling of metastable neon atoms confined to the dark center of a ${\mathrm{TEM}}_{01}^{*}$ (doughnut) mode. A slow beam of neon atoms is guided and focused inside a blue-detuned and focused doughnut-mode laser beam to a spot size below 10 \ensuremath{\mu}m. The transverse motion inside this doughnut mode is cooled by means of two-dimensional optical molasses. We observed non-Gaussian two-component velocity distributions of which the cold component has a width of down to three recoil velocities. These results are found to be in qualitative agreement with a quantum Monte Carlo simulation of cooling in one dimension in the presence of an external light-shift potential. For the simulation we apply the recently developed technique of quantum-state diffusion with adaptive noise.We present experimental and theoretical studies of polarization-gradient cooling of metastable neon atoms confined to the dark center of a ${\mathrm{TEM}}_{01}^{*}$ (doughnut) mode. A slow beam of neon atoms is guided and focused inside a blue-detuned and focused doughnut-mode laser beam to a spot size below 10 \ensuremath{\mu}m. The transverse motion inside this doughnut mode is cooled by means of two-dimensional optical molasses. We observed non-Gaussian two-component velocity distributions of which the cold component has a width of down to three recoil velocities. These results are found to be in qualitative agreement with a quantum Monte Carlo simulation of cooling in one dimension in the presence of an external light-shift potential. For the simulation we apply the recently developed technique of quantum-state diffusion with adaptive noise.

Physical Review AOct 1, 199854 citations

Prospects of Trapping Atoms with an Optical Dipole Trap in a Deep Parabolic Mirror for Light–Matter‐Interaction Experiments

Markus Sondermann, Martin Fischer, Gerd Leuchs

Abstract The prospects of employing a deep parabolic mirror as a focusing device for trapping neutral atoms in an optical dipole trap are evaluated. It is predicted that such a dipole trap will result in a deep trapping potential as well as in a small spatial spread of the atom's center of mass wave function already for a Doppler cooled atom. This strong confinement is beneficial for many applications, one of which is the increase of the interaction strength between an atom and a light field focused from full solid angle.Abstract The prospects of employing a deep parabolic mirror as a focusing device for trapping neutral atoms in an optical dipole trap are evaluated. It is predicted that such a dipole trap will result in a deep trapping potential as well as in a small spatial spread of the atom's center of mass wave function already for a Doppler cooled atom. This strong confinement is beneficial for many applications, one of which is the increase of the interaction strength between an atom and a light field focused from full solid angle.

Advanced Quantum TechnologiesMay 10, 20204 citations

Cooling and trapping of neutral atoms

Harold J. Metcalf, P. van der Straten

Physics ReportsAug 1, 1994254 citations

Cooling and Trapping Atoms

William D. Phillips, Harold J. Metcalf

Scientific AmericanMar 1, 198737 citations

Experimental Investigation of the Influence of the Laser Beam Waist on Cold Atom Guiding Efficiency

Ningfang Song, Di Hu, Xiaobin Xu +3 more

The primary purpose of this study is to investigate the influence of the vertical guiding laser beam waist on cold atom guiding efficiency. In this study, a double magneto-optical trap (MOT) apparatus is used. With an unbalanced force in the horizontal direction, a cold atomic beam is generated by the first MOT. The cold atoms enter the second chamber and are then re-trapped and cooled by the second MOT. By releasing a second atom cloud, the process of transferring the cold atoms from MOT to the dipole trap, which is formed by a red-detuned converged 1064-nm laser, is experimentally demonstrated. And after releasing for 20 ms, the atom cloud is guided to a distance of approximately 3 mm. As indicated by the results, the guiding efficiency depends strongly on the laser beam waist; the efficiency reaches a maximum when the waist radius (w0) of the laser is in the range of 15 to 25 μm, while the initial atom cloud has a radius of 133 μm. Additionally, the properties of the atoms inside the dipole potential trap, such as the distribution profile and lifetime, are deduced from the fluorescence images.The primary purpose of this study is to investigate the influence of the vertical guiding laser beam waist on cold atom guiding efficiency. In this study, a double magneto-optical trap (MOT) apparatus is used. With an unbalanced force in the horizontal direction, a cold atomic beam is generated by the first MOT. The cold atoms enter the second chamber and are then re-trapped and cooled by the second MOT. By releasing a second atom cloud, the process of transferring the cold atoms from MOT to the dipole trap, which is formed by a red-detuned converged 1064-nm laser, is experimentally demonstrated. And after releasing for 20 ms, the atom cloud is guided to a distance of approximately 3 mm. As indicated by the results, the guiding efficiency depends strongly on the laser beam waist; the efficiency reaches a maximum when the waist radius (w0) of the laser is in the range of 15 to 25 μm, while the initial atom cloud has a radius of 133 μm. Additionally, the properties of the atoms inside the dipole potential trap, such as the distribution profile and lifetime, are deduced from the fluorescence images.

SensorsFeb 28, 20181 citation

We present experimental and theoretical studies of polarization-gradient cooling of metastable neon atoms confined to the dark center of a

{\mathrm{TEM}}_{01}^{*}

(doughnut) mode. A slow beam of neon atoms is guided and focused inside a blue-detuned and focused doughnut-mode laser beam to a spot size below 10 \ensuremath{\mu}m. The transverse motion inside this doughnut mode is cooled by means of two-dimensional optical molasses. We observed non-Gaussian two-component velocity distributions of which the cold component has a width of down to three recoil velocities. These results are found to be in qualitative agreement with a quantum Monte Carlo simulation of cooling in one dimension in the presence of an external light-shift potential. For the simulation we apply the recently developed technique of quantum-state diffusion with adaptive noise.