Abstract

In a one-dimensional polarization-gradient cooling scheme, with two counter-propagating laser beams having mutually orthogonal linear polarization, a linear array of potential wells for cold atoms are formed. These optical potential wells are created by the spatially varying light shift of the atomic ground state. Transitions between quantized vibrational states in such wells have been observed by stimulated¹ and spontaneous² Raman spectroscopy. Recently, this was extended to three dimensions using both four beams³ and six beams.⁴ In this work, we intersect four travelling-wave laser beams, all polarized in the same plane, as indicated in Fig. 1. This produces a threedimensional body-centered cubic lattice of potential wells for cesium atoms. The laser wavelength is tuned 25 linewidths below the 6²S_1/2(F = 4) → 6²P_3/2(F = 5) transition at 852 nm; and the resultant lattice constants (distances between wells of the same character) are $\lambda /\sqrt{2}$ perpendicular to the plane of polarization, and $\lambda \times \sqrt{2}$ in the plane of polarization.

© 1994 Optical Society of America