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Atoms from an otherwise unconfined 87Rb condensate are shown to be suspended against gravity using repeated reflections from a pulsed optical standing wave. Reflection efficiency was optimized using a triple-pulse sequence that, theoretically, provides accuracies better than 99.9%. Experimentally, up to 100 reflections are observed, leading to dynamical suspension for over 100 ms. The velocity sensitivity of the reflections can be used to determine the local gravitational acceleration. Further, a gravitationally sensitive atom interferometer was implemented using the suspended atoms, with packet coherence maintained for a similar time. These techniques could be useful for the precise measurement of gravity when it is impractical to allow atoms to fall freely over a large distance.
The motion of metastable helium atoms travelling through a standing light wave is investigated with a semi-classical numerical model. The results of a calculation including the velocity dependence of the dipole force are compared with those of the co
We have created periodic nanoscale structures in a gold substrate with a lithography process using metastable triplet helium atoms that damage a hydrofobic resist layer on top of the substrate. A beam of metastable helium atoms is transversely cooled
We trap a single cesium atom in a standing-wave optical dipole trap. Special experimental procedures, designed to work with single atoms, are used to measure the oscillation frequency and the atomic energy distribution in the dipole trap. These metho
A Bose-Einstein condensate is used as an atomic source for a high precision sensor. A $5times 10^6$ atom F=1 spinor condensate of $^{87}$Rb is released into free fall for up to $750$ms and probed with a Mach-Zehnder atom interferometer based on Bragg
We show that properly detuning the carrier frequency of each of the criss-cross bichromatic waves from the transition frequency of the atom, it is possible to form a two-dimensional trap for atoms if the intensity of the waves is sufficiently large.