STANDING LIGHT FIELDS FOR COLD ATOMS WITH INTRINSICALLY STABLE AND VARIABLE TIME PHASES

We present a novel method to realise a standing light field with a sta ble configuration in two or three dimensions. A single standing wave f ormed by two counterpropagating beams is folded and br ought into inte rsection with itself. The values of the relative timephases are stable , a priori known, and can be altered arbitrarily by means of retardati on plates. The polarisation configurations of three orthogonal standin g waves include the standard magnetooptical trap and a novel three-dim ensional pure polarisation lattice which we have investigated in a fir st spectroscopic measurement, providing strong evidence for atomic loc alisation in both cases. (C) 1998 Elsevier Science B.V.