Optical Ferris wheel

(May 2007) The overlap of two laser beams creates both constructive and destructive interference. For Laguerre-Gaussian modes, the resulting patterns appear as a circular array of petals. We have now shown that it the beams are chosen correctly, the destructive interference forms a circular array of dark holes, ideal for trapping atoms at very low temperatures. Shifting the frequency between the beam causes the pattern to rotate, creating what we call an "Optical Ferris wheel".

• movie
• S. Franke-Arnold, J. Leach, M. J. Padgett, V. E. Lembessis, D. Ellinas, A. J. Wright, J. M. Girkin, P. Öhberg and A. S. Arnold, Optical ferris wheel for ultracold atoms, Opt. Express 15, 8619-8625 (2007)