Cooperative effects on Optical forces- Dicke’s bullet

Published Jan 1, 2001• 3 citations

Abstract

We investigate the cooperative effects on optical forces in a system of N two level atoms confined to a volume of dimension less than λ 3, where λ is radiation wavelength and driven by a coherent radiation field with a spatial profile like Laguerre-Gaussian or ideal Bessel beam. We show a dramatic enhancement on optical forces as well as the angular momentum imparted to the atom by a factor of N 2. PACS number(s) 42.50 FX, 32.80 Pj 1 Recently, there is a considerable interest in cooling and trapping of alkali atoms at low temperatures and subsequent observation of Bose-Einstein (BEC) condensation[1,2] which has a property of a generating laser like source of matter waves. As demonstrated by S. Inoyu et. al., these neutral matter waves confined in a cigar shaped BEC[3] show a highly directional super radiant Rayleigh scattering when pumped by an off resonant laser beam[4]. This is attributed to a cooperative effect due to

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