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AIP conference proceedings

Observation of quantized motion of atoms in optical molasses

S. L. Rolston, Christoph Gerz, Paul D. Lett, William D. Phillips, R. J. C. Spreeuw, Christoph Ira Westbrook, Poul Jessen

Published Jan 1, 1993• 0 citations
Publisher

Abstract

We have observed the quantized motion of atoms trapped in wavelength‐sized optical potential wells. Using high‐resolution spectroscopy of the resonance fluorescence of laser‐cooled Rb atoms, we have identified spontaneous Raman transitions between bound vibrational levels. From the fluorescence spectrum, we can measure the spacing of the vibrational levels, population distributions and temperatures, and determine that the atoms are localized to λ/15. These measurements are in excellent quantitative agreement with recent quantum Monte Carlo calculations.

DOI
10.1063/1.43793

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We have observed the quantized motion of atoms trapped in wavelength‐sized optical potential wells. Using high‐resolution spectroscopy of the resonance fluorescence of laser‐cooled Rb atoms, we have identified spontaneous Raman transitions between bound vibrational levels. From the fluorescence spectrum, we can measure the spacing of the vibrational levels, population distributions and temperatures, and determine that the atoms are localized to λ/15. These measurements are in excellent quantitative agreement with recent quantum Monte Carlo calculations.
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We study theoretically the spectrum of resonance fluorescence and laser-cooling dynamics corresponding to quantized atomic motion in one-dimensional optical molasses. We consider an atom with a Jg{\mathit{J}}_{\mathit{g}}Jg​=1\ensuremath{\rightarrow}Je{\mathit{J}}_{\mathit{e}}Je​=2 transition interacting with two counterpropagating laser beams. The laser light is assumed to be linearly polarized with an angle \ensuremath{\theta} between the polarization vectors. We discuss the spectrum of resonance fluorescence, the spectroscopy of band structure in the optical potentials, and the population of the vibrational quantum levels as a function of the angle between the polarization vectors.
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