Ballistic peaks at quantum resonance
نویسندگان
چکیده
We report studies of the motion of cold atoms in a time-dependent optical potential. The dynamics of our system are that of the quantum kicked rotor, and exhibit a wide variety of phenomena. One purely quantum effect is the quantum resonance, which occurs for well-chosen initial conditions and specific values of the period between kicks. Distinctly nonclassical behavior, such as ballistic growth in momentum, is possible at a quantum resonance. Previous experimental studies have observed these resonances, but have not clearly resolved the expected ballistic motion. We now observe ballistic motion at quantum resonances and compare our momentum distributions with theory and numerical simulations. q 2000 Elsevier Science B.V. All rights reserved. PACS: 05.45.qb; 32.80.Pj; 42.50.Vk; 72.15.Rn
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