Stabilizing an atom laser using spatially selective pumping and feedback

Stabilizing an atom laser using spatially selective pumping and feedback

We perform a comprehensive study of stability of a pumped atom laser in the presence of pumping, damping, and outcoupling. We also introduce a realistic feedback scheme to improve stability by extracting energy from the condensate and determine its effectiveness. We find that while the feedback scheme is highly efficient in reducing condensate fluctuations, it usually does not alter the stabili...

Feedback control of an atom laser.

We report the first real-time feedback control of an atom laser. The unique feature of metastable helium atoms, the production of ions in the atom laser outcoupling process, is exploited to actively control the spatial location inside the Bose-Einstein condensate where outcoupling occurs. Unlike alkali atom lasers, this provides almost instantaneous feedback which reduces frequency, amplitude a...

Reducing the linewidth of an atom laser by feedback.

A continuous atom laser will almost certainly have a linewidth dominated by the effect of the atomic interaction energy, which turns fluctuations in the condensate atom number into fluctuations in the condensate frequency. These correlated fluctuations mean that information about the atom number could be used to reduce the frequency fluctuations, by controlling a spatially uniform potential. We...

Reducing the Linewidth of an Atom Laser by Feedback

An Atom Trap Relying on Optical Pumping . ∗

We have investigated a new radiation pressure trap which relies on optical pumping and does not require any magnetic field. It employs six circularly polarized divergent beams and works on the red of a Jg −→ Je = Jg + 1 atomic transition with Jg ≥ 1/2. We have demonstrated this trap with cesium atoms from a vapour cell using the 852 nm Jg = 4 −→ Je = 5 resonance transition. The trap contained u...