Abstract
The recent demonstration of cooling and manipulation techniques for molecules offer newpossibilities for precision measurements in molecules. Here, we present the design of a molecularfountain based on a Stark decelerated molecular beam. In this fountain, ammonia molecules aredecelerated to a few meter per second, cooled to sub microKelvin temperatures and subsequentlylaunched. The molecules fly upwards some 30 cm before falling back under gravity, thereby passing amicrowave cavity twice – as they fly up and as they fall back down. The effective interrogationtime in such a Ramsey type measurement scheme includes the entire flight time between the twotraversals through the driving field, which is on the order of a 1/2 second. We present numericalsimulations of the trajectories through the decelerator and estimate the expected count rate. Wepresent an evaluation of the expected stability and accuracy for the inversion transition in15NH3 around 22.6 GHz. The estimated frequency instability is \(7\times10^{-12}~\tau^{-1/2}\), with τ being the measurement time in seconds. With a careful design ofthe interogation zone, systematic frequency shifts are kept below 10-14. Besides serving as aproof-of-principle, these measurements may be used as a test of the time-variation of fundamentalconstants using the sensitivity of the tunneling motion to a change of the proton-electron massratio.
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References
S. Bize, et al., J. Phys. B. – Atom. Mol. Opt. Phys. 38, S449 (2005)
T.P. Heavner, et al., Metrologia 42, 411 (2005)
M.M. Boyd, et al., Phys. Rev. Lett. 98, 083002 (2007)
W.H. Oskay, et al., Phys. Rev. Lett. 97, 020801 (2006)
H.L. Bethlem, G. Meijer, Int. Rev. Phys. Chem. 22, 73 (2003)
J. Doyle, B. Friedrich, R.V. Krems, F. Masnou-Seeuws, Eur. Phys. J. D 31, 149 (2004)
J. van Veldhoven, J. Küpper, H.L. Bethlem, B. Sartakov, A.J. van Roij, G. Meijer, Eur. Phys. J. D 31, 337 (2004)
E.R. Hudson, H.J. Lewandowski, B.C. Sawyer, J. Ye, Phys. Rev. Lett. 96, 143004 (2006)
J.J. Hudson, B.E. Sauer, M.R. Tarbutt, E.A. Hinds, Phys. Rev. Lett. 89, 023003 (2002)
D. Kawall, F. Bay, S. Bickman, Y. Jiang, D. DeMille, Phys. Rev. Lett. 92, 133007 (2004)
D. DeMille, S.B. Cahn, D. Murphree, D.A. Rahmlow, M.G. Kozlov, Phys. Rev. Lett. 100, 023003 (2008)
Ch. Daussy, et al., Phys. Rev. Lett. 83, 1554 (1999)
A. Shelkovnikov, R.J. Butcher, C. Chardonnet, A. Amy-Klein, Phys. Rev. Lett. 100, 150801 (2008)
V.V. Flambaum, Eur. Phys. J. Special Topics 163, 159 (2008)
P. Foreman, Proc. IEEE 73, 1181 (1985)
J.P. Gordon, H.J. Zeiger, C.H. Townes, Phys. Rev. 99, 1264 (1955)
S.G. Kukolich, Phys. Rev. 156, 83 (1967)
J.T. Hougen, J. Chem. Phys. 156, 83 (1972)
J. van Veldhoven, R.T. Jongma, B. Sartakov, W.A. Bongers, G. Meijer, Phys. Rev. A 66, 032501 (2002)
S. Urban, J. Quant. Spec. Rad. Trans. 48, 675 (1992)
C.H. Townes, A.L. Schawlow, Microwave Spectroscopy (McGraw-Hill, New York, 1955)
H.L. Bethlem, F.M.H. Crompvoets, R.T. Jongma, S.Y.T. van de Meerakker, G. Meijer, Phys. Rev. A 65, 053416 (2002)
F.M.H. Crompvoets, R.T. Jongma, H.L. Bethlem, G. Meijer, Phys. Rev. Lett. 89, 093004 (2002)
M.N.R. Ashfold, R.N. Dixon, N. Little, R.J. Stickland, C.M. Western, J. Chem. Phys. 89, 1754 (1988)
J. Vanier, C. Audoin, The Quantum Physics of Atomic Frequency Standard (IOP Publishing, Bristol, 1989)
M. Kajita, Phys. Rev. A 74, 032710 (2006)
W.M. Itano, L.L. Lewis, D.J. Wineland, Phys. Rev. A 25, 1233 (1982)
S. Hoekstra, et al., Phys. Rev. Lett. 98, 133001 (2007)
N. Vanhaecke, O. Dulieu, Mol. Phys. 105, 1723 (2007)
S. Urban, D. Papousek, V.M. Devi, B. Fridovich, R. D’Cunha, K.N. Rao, J. Mol. Spectrosc. 86, 38 (1984)
S.R. Jefferts, R.E. Drullinger, A. DeMarchi, Proc. IEEE Int. Freq. Control Symp. (1998)
J.K. Webb, et al., Phys. Rev. Lett. 87, 091301 (2001)
E. Reinhold, R. Buning, U. Hollenstein, A. Ivanchik, P. Petitjean, W. Ubachs, Phys. Rev. Lett. 96, 151101 (2006)
E. Peik, S. Karshenboim, Eur. Phys. J. Special Topics 163, 1 (2008)
X. Calmet, H. Fritzsch, Eur. Phys. J. C 24, 693 (2002)
J.-P. Uzan, Rev. Mod. Phys. 75, 403 (2003)
P. Helminger, F.C. DeLucia, W. Gordy, H.W. Morgan, P.A. Staats, Phys. Rev. A 9, 12 (1974)
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Bethlem, H., Kajita, M., Sartakov, B. et al. Prospects for precision measurements on ammonia molecules in a fountain. Eur. Phys. J. Spec. Top. 163, 55–69 (2008). https://doi.org/10.1140/epjst/e2008-00809-5
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DOI: https://doi.org/10.1140/epjst/e2008-00809-5