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Coherent Delocalization of Atomic Wave Packets in Driven Lattice Potentials

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 نشر من قبل Gabriele Ferrari
 تاريخ النشر 2008
  مجال البحث فيزياء
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Atomic wave packets loaded into a phase-modulated vertical optical-lattice potential exhibit a coherent delocalization dynamics arising from intraband transitions among Wannier-Stark levels. Wannier-Stark intraband transitions are here observed by monitoring the in situ wave-packet extent. By varying the modulation frequency, we find resonances at integer multiples of the Bloch frequency. The resonances show a Fourier-limited width for interrogation times up to 2 s. This can also be used to determine the gravity acceleration with ppm resolution.



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