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Register a new userDouble diffraction in an atomic gravimeter
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Added by
Franck Pereira Dos Santos
Publication date
2009
fields
Physics
and research's language is
English
Authors
Nicola Malossi
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We demonstrate the realization of a new scheme for cold atom gravimetry based on the use of double diffraction beamsplitters recently demonstrated in cite{Leveque}, where the use of two retro-reflected Raman beams allows symmetric diffraction in $pm hbar k_{eff}$ momenta. Though in principle restricted to the case of zero Doppler shift, for which the two pairs of Raman beams are simultaneously resonant, we demonstrate that such diffraction pulses can remain efficient on atoms with non zero velocity, such as in a gravimeter, when modulating the frequency of one of the two Raman laser sources. We use such pulses to realize an interferometer insensitive to laser phase noise and some of the dominant systematics. This reduces the technical requirements and would allow the realization of a simple atomic gravimeter. We demonstrate a sensitivity of $1.2times10^{-7}g$ per shot.
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