Quantum Information Processing, Vol. 5, No. 6, December 2006 (© 2006)
A Double Well Interferometer on an Atom Chip
P. K r
L. M. Andersson,
and J. Schmiedmayer
Received May 9, 2006; accepted May 11, 2006; Published online August 29, 2006
Radio-Frequency coupling between magnetically trapped atomic states allows to
create versatile adiabatic dressed state potentials for neutral atom manipulation.
Most notably, a single magnetic trap can be split into a double well by control-
ling amplitude and frequency of an oscillating magnetic ﬁeld. We use this to build
an integrated matter wave interferometer on an atom chip. Transverse splitting
of quasi one-dimensional Bose–Einstein condensates over a wide range from 3 to
80 µm is demonstrated, accessing the tunnelling regime as well as completely iso-
lated sites. By recombining the two split BECs in time of ﬂight expansion, we
realize a matter wave interferometer. The observed interference pattern exhibits a
stable relative phase of the two condensates, clearly indicating a coherent splitting
process. Furthermore, we measure and control the deterministic phase evolution
throughout the splitting process. RF induced potentials are especially suited for
integrated micro manipulation of neutral atoms on atom chips: designing appro-
priate wire patterns enables control over the created potentials to the (nanome-
ter) precision of the fabrication process. Additionally, hight local RF amplitudes
can be obtained with only moderate currents. This new technique can be directly
implemented in many existing atom chip experiments.
KEY WORDS: Atom waves; atom interferometry; Bose–Einstein condensation;
double well; atom chips.
PACS: 03.75.-b; 03.75.Nt; 39.20+q.
Physikalisches Institut, Universit
at Heidelberg, D-69120 Heidelberg, Germany.
aten, TU-Wien, 1040 Vienna, Austria.
McLennan Physical Labs, University of Toronto, Ontario, M5S1A7 Canada.
Laboratoire Kastler Brossel,
Ecole Normale Sup
erieure, F-75005 Paris, France.
Department of Condensed Matter Physics, The Weizmann Institute of Science, Rehovot
Department of Microelectronics and Information Technology, The Royal Institute of Tech-
nology, SE-164 40, Kista, Sweden.
To whom correspondence should be addressed. E-mail: firstname.lastname@example.org-
1570-0755/06/1200-0537/0 © 2006 Springer Science+Business Media, Inc.