A low velocity intense source (LVIS) of cold rubidium atoms is guided along a co-propagating far-off resonance light guide. An 8% enhancement of the guided atomic flux is observed in the steady state. Data are presented for the transient response of the LVIS to the guide beam observing a non-adiabatic kick and a transient 25% enhancement of the guided flux. A characteristic decay time of 0.45 s is recorded for the return to the steady state flux.
A low velocity intense source (LVIS) of cold rubidium atoms is guided along a co-propagating far-off resonance light guide. An 8% enhancement of the guided atomic flux is observed in the steady state. Data are presented for the transient response of the LVIS to the guide beam observing a non-adiabatic kick and a transient 25% enhancement of the guided flux. A characteristic decay time of 0.45 s is recorded for the return to the steady state flux.
We investigate experimentally and numerically the quantitative dependence of characteristics of a low-velocity intensity source (LVIS) of atomic beam on light parameters, especially the polarization of cooling laser along the atomic beam axis (pushing beam). By changing the polarization of the pushing beam, the longitudinal mean velocity of a rubidium atomic beam can be tuned continuously from 10 to 20 m/s and the flux can range from 3 × 10 8 to 1 × 10 9 atoms/s, corresponding to the maximum sensitivity of the velocity with respect to the polarization angle of 20 (m/s)/rad and the mean sensitivity of flux of 1.2 × 10 9 (atoms/s)/rad. The mechanism is explained with a Monte-Carlo based numerical simulation method, which shows a qualitative agreement with the experimental result. This is also a demonstration of a method enabling the fast and continuous modulation of a low-velocity intense source of cold atomic beam on the velocity or flux, which can be used in many fields, like the development of a cold atomic beam interferometer and atom lithography.
Summary form only given. The widespread use of magneto-optical traps (MOT) and the development of BEC over the last 10 years have led to the field of atom optics. This field requires the use of equivalent elements to optical mirrors, lenses and beam splitters. The generation of a large deviation atomic beam splitter is one of the most important goals, as it allows the construction of atom interferometers. Optical methods for achieving these elements are enticing, as the use of laser beams would make it easier to alter parameters of your guides within a vacuum chamber. Recent work has demonstrated the use of optical beams to guide and split atoms from a cold atom source. Here we present novel experimental studies of the optical guiding (in both the red- and blue-detuned regime) of a low-velocity intense source (LVIS) of atoms emanating from a rubidium MOT.
We present the implementation and characterization of a slow, intense, and collimated rubidium atomic source for atom interferometry. The continuous87Rb cold atomic beam is produced by a new compact two-dimensional magneto-optical trap. And it is based on the 2D+MOT design but a much smaller size and a higher flux compared to our original LVIS system. The on-line detecting system developed over a combination of time-of-flight and fluorescence methods is used to optimize the beam parameters. The dependence of the beam flux on detuning and power are investigated in detail respectively, for cooling and pushing laser. The re-pumping laser power influence is also considered. With aError! Reference source not found.10 G/cm magnetic gradient, 3ΓError! Reference source not found. red detuning from resonance for cooling laser and 5ΓError! Reference source not found. red detuning for pushing laser, the obtained cold atomic beam has a high flux of 4.7×109atoms/s Error! Reference source not found. Error! Reference source not found. It has a narrow longitudinal velocity distribution with mean velocity 10 m/s and full width at half maximum (FWHM)Error! Reference source not found.2 m/sError! Reference source not found. The two-photo stimulated Raman transitions both in Doppler-free and Doppler-sensitive modes are first proceeded, and stable Raman-Ramsey fringes are achieved with twon/2 Error! Reference source not found. Raman pulses.
We produced a slow atomic beam of rubidium with a low-velocity intense source (LVIS) and loaded a magneto-optical trap (MOT) in a connected chamber with the beam. The hole for the atomic beam allowed us to keep the MOT chamber at a much lower pressure than that of the LVIS. The LVIS produced an atomic beam with a continuous flux of (4.3±0.4)×109/s and an average velocity of only 11±3 m/s. The MOT captured the atoms with 67±15% efficiency, which was limited by the atomic-beam divergence. The MOT held 6×109 atoms with a typical trap-confinement time of 8 s.
We present a cold atomic beam source based on a two-dimensional (2D)+ magneto-optical trap (MOT), capable of generating a continuous cold beam of 87Rb atoms with a flux up to 4.3*10^9 atoms/s, a mean velocity of 10.96(2.20) m/s, and a transverse temperature of 16.90(1.56) uK. Investigating the influence of high cooling laser intensity, we observe a significant population loss of atoms to hyperfine-level dark states. To account for this, we employ a multiple hyperfine level model to calculate the cooling efficiency associated with the population in dark states, subsequently modifying the scattering force. Simulations of beam flux at different cooling and repumping laser intensities using the modified scattering force are in agreement with experimental results. Optimizing repumping and cooling intensities enhances the flux by 50%. The influence of phase modulation on both the pushing and cooling lasers is experimentally studied, revealing that the mean velocity of cold atoms can be tuned from 9.5 m/s to 14.6 m/s with a phase-modulated pushing laser. The versatility of this continuous beam source, featuring high flux, controlled velocity, and narrow transverse temperature, renders it valuable for applications in atom interferometers and clocks, ultimately enhancing bandwidth, sensitivity, and signal contrast in these devices.
, a mean velocity of 10.96(2.20) m/s, and a transverse temperature of 16.90(1.56) µK. Investigating the influence of high cooling laser intensity, we observe a significant population loss of atoms to hyperfine-level dark states. To account for this, we employ a multiple hyperfine level model to calculate the cooling efficiency associated with the population in dark states, subsequently modifying the scattering force. Simulations of beam flux at different cooling and repumping laser intensities using the modified scattering force are in agreement with experimental results. Optimizing repumping and cooling intensities enhances the flux by 50%. The influence of phase modulation on both the pushing and cooling lasers is experimentally studied, revealing that the mean velocity of cold atoms can be tuned from 9.5 m/s to 14.6 m/s with a phase-modulated pushing laser. The versatility of this continuous beam source, featuring high flux, controlled velocity, and narrow transverse temperature, renders it valuable for applications in atom interferometers and clocks, ultimately enhancing bandwidth, sensitivity, and signal contrast in these devices.