We measure the rates of elastic and inelastic two-body collisions of cold spin-polarized neon atoms in the metastable $^{3}P_{2}$ state for $^{20}\mathrm{Ne}$ and $^{22}\mathrm{Ne}$ in a magnetic trap. From particle loss, we determine the loss parameter of inelastic collisions $\ensuremath{\beta}=6.5(18)\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}12}\text{ }\text{ }{\mathrm{cm}}^{3}\text{ }{\mathrm{s}}^{\ensuremath{-}1}$ for $^{20}\mathrm{Ne}$ and $\ensuremath{\beta}=1.2(3)\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}11}\text{ }\text{ }{\mathrm{cm}}^{3}\text{ }{\mathrm{s}}^{\ensuremath{-}1}$ for $^{22}\mathrm{Ne}$ . These losses are caused by ionizing (i.e., Penning) collisions and occur less frequently than for unpolarized atoms. This proves the suppression of Penning ionization due to spin polarization. From cross-dimensional relaxation measurements, we obtain elastic scattering lengths of $a=\ensuremath{-}180(40){a}_{0}$ for $^{20}\mathrm{Ne}$ and $a=+{150}_{\ensuremath{-}50}^{+80}{a}_{0}$ for $^{22}\mathrm{Ne}$ , where ${a}_{0}=0.0529\text{ }\text{ }\mathrm{nm}$ .We measure the rates of elastic and inelastic two-body collisions of cold spin-polarized neon atoms in the metastable $^{3}P_{2}$ state for $^{20}\mathrm{Ne}$ and $^{22}\mathrm{Ne}$ in a magnetic trap. From particle loss, we determine the loss parameter of inelastic collisions $\ensuremath{\beta}=6.5(18)\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}12}\text{ }\text{ }{\mathrm{cm}}^{3}\text{ }{\mathrm{s}}^{\ensuremath{-}1}$ for $^{20}\mathrm{Ne}$ and $\ensuremath{\beta}=1.2(3)\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}11}\text{ }\text{ }{\mathrm{cm}}^{3}\text{ }{\mathrm{s}}^{\ensuremath{-}1}$ for $^{22}\mathrm{Ne}$. These losses are caused by ionizing (i.e., Penning) collisions and occur less frequently than for unpolarized atoms. This proves the suppression of Penning ionization due to spin polarization. From cross-dimensional relaxation measurements, we obtain elastic scattering lengths of $a=\ensuremath{-}180(40){a}_{0}$ for $^{20}\mathrm{Ne}$ and $a=+{150}_{\ensuremath{-}50}^{+80}{a}_{0}$ for $^{22}\mathrm{Ne}$, where ${a}_{0}=0.0529\text{ }\text{ }\mathrm{nm}$.

arXiv:quant-ph/0502020Physical Review LettersJun 7, 200525 citations

We measure the rates of elastic and inelastic two-body collisions of cold spin-polarized neon atoms in the metastable

^{3}P_{2}

state for

^{20}\mathrm{Ne}

and

^{22}\mathrm{Ne}

in a magnetic trap. From particle loss, we determine the loss parameter of inelastic collisions $\ensuremath{\beta}=6.5(18)\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}12}\text{ }\text{ }{\mathrm{cm}}^{3}\text{ }{\mathrm{s}}^{\ensuremath{-}1}$ for

^{20}\mathrm{Ne}

and $\ensuremath{\beta}=1.2(3)\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}11}\text{ }\text{ }{\mathrm{cm}}^{3}\text{ }{\mathrm{s}}^{\ensuremath{-}1}$ for

^{22}\mathrm{Ne}

. These losses are caused by ionizing (i.e., Penning) collisions and occur less frequently than for unpolarized atoms. This proves the suppression of Penning ionization due to spin polarization. From cross-dimensional relaxation measurements, we obtain elastic scattering lengths of $a=\ensuremath{-}180(40){a}_{0}$ for

^{20}\mathrm{Ne}

and $a=+{150}_{\ensuremath{-}50}^{+80}{a}_{0}$ for

^{22}\mathrm{Ne}

, where

{a}_{0}=0.0529\text{ }\text{ }\mathrm{nm}