Creating a self-induced dark spontaneous-force optical trap for neutral atoms

• Published in: Optics communications Vol. 235; no. 4; pp. 333 - 340
• Main Authors: Muniz, S.R., Magalhães, K.M.F., Henn, E.A.L., Marcassa, L.G., Bagnato, V.S.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 15.05.2004; Elsevier Science
• Subjects: Atomic and molecular physics; Atomic properties and interactions with photons; Dark SPOT; Exact sciences and technology; High-density MOT; Optical cooling of atoms; trapping; Optical pumping; Photon interactions with atoms; Physics; High-density MOT; Optical pumping; Dark SPOT; 32.80.Pj; Light matter interaction; Laser pumping; Optical transition; Laser cooling; Experimental device; Experimental study; Laser beams; Gaussian beam; Optical trapping; Measurement systems; Magnetooptical trap; Atom trapping
• ISSN: 0030-4018; 1873-0310
• DOI: 10.1016/j.optcom.2004.02.062

This communication describes the observation of a new type of dark spontaneous-force optical trap (dark SPOT) obtained without the use of a mask blocking the central part of the repumper laser beam. We observe that loading a magneto-optical trap from a continuous and intense flux of slowed atoms and by appropriately tuning the frequency of the repumper laser is possible to achieve basically the same effect of the dark SPOT, using a simpler apparatus. This work characterizes the new system through measurements of absorption and fluorescence imaging of the atomic cloud and presents a very simple model to explain the main features of our observations. We believe that this new approach may simplify the current experiments to produce quantum degenerated gases.