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Determination of the s-wave Scattering Length of Chromium

P. O. Schmidt·S. Hensler·J. Werner·A. Griesmaier·A. Goerlitz·T. Pfau·A. Simoni
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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 $|a(^{52}Cr)|=(170 \pm 39)a_0$ and $|a(^{50}Cr)|=(40 \pm 15)a_0$, 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.

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P. O. Schmidt, S. Hensler, J. Werner, A. Griesmaier, A. Goerlitz, T. Pfau, A. Simoni. 2003-04-06. Determination of the s-wave Scattering Length of Chromium. https://doi.org/10.1103/physrevlett.91.193201

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