Enhanced and reduced atom number fluctuations in a BEC splitter.
We measure atom number statistics after splitting a gas of ultracold 87Rb atoms in a purely magnetic double-well potential created on an atom chip. Well below the critical temperature for Bose-Einstein condensation Tc, we observe reduced fluctuations down to -4.9 dB below the atom shot noise level. Fluctuations rise to more than +3.8 dB close to Tc, before reaching the shot noise level for higher temperatures. We use two-mode and classical field simulations to model these results. This allows us to confirm that the supershot noise fluctuations directly originate from quantum statistics.
Maussang
Kenneth
K
Laboratoire Kastler-Brossel, ENS, Université Pierre et Marie Curie-Paris 6, CNRS, 24 rue Lhomond, 75 231 Paris Cedex 05, France.
Marti
G Edward
GE
Schneider
Tobias
T
Treutlein
Philipp
P
Li
Yun
Y
Sinatra
Alice
A
Long
Romain
R
Estève
Jérôme
J
Reichel
Jakob
J