Determination of the s-wave Scattering Length of Chromium
P.O. Schmidt, S. Hensler, J. Werner, A. Griesmaier, A. Goerlitz, T. Pfau, A. Simoni
Abstract
We have measured the deca-triplet s-wave scattering length of the bosonic chromium isotopes
52
Cr and
50
Cr. From the time constants for cross-dimensional thermalization in atomic samples we have determined the magnitudes
|a
(
52
Cr)|=(170±39)
a
0
and
|a
(
50
Cr)|=(40±15)
a
0
, where
a
0
=0.053nm
. By measuring the rethermalization rate of
52
Cr over a wide temperature range and comparing the temperature dependence with the effective-range theory and single-channel calculations, we have obtained strong evidence that the sign of
a
(
52
Cr)
is positive. Rescaling our
52
Cr model potential to
50
Cr strongly suggests that
a
(
50
Cr)
is positive, too.