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Limits to the sensitivity of a low noise compact atomic gravimeter

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 نشر من قبل Franck Pereira Dos Santos
 تاريخ النشر 2008
  مجال البحث فيزياء
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A detailed analysis of the most relevant sources of phase noise in an atomic interferometer is carried out, both theoretically and experimentally. Even a short interrogation time of 100 ms allows our cold atom gravimeter to reach an excellent short term sensitivity to acceleration of $1.4times 10^{-8}$g at 1s. This result relies on the combination of a low phase noise laser system, efficient detection scheme and good shielding from vibrations. In particular, we describe a simple and robust technique of vibration compensation, which is based on correcting the interferometer signal by using the AC acceleration signal measured by a low noise seismometer.

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