Unitarity-limited elastic collision rate in a harmonically trapped Fermi gas
Unitarity-limited elastic collision rate in a harmonically trapped Fermi gas
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DOI：
10.1103/physreva.68.011603
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发表时间：
2003-04
影响因子：
2.9
通讯作者：
M. Gehm;S. Hemmer;K. O’Hara;J. Thomas
中科院分区：
文献类型：
--
作者：
M. Gehm;S. Hemmer;K. O’Hara;J. Thomas
我们推导了调和俘获费米气体在极端幺正性极限下的弹性碰撞率，其中 s 波散射截面为 {sigma}(k)=4{pi}/k{sup 2}，其中 ({Dirac_h}/2{pi})k 为相对动量。碰撞率以 {gamma}={gamma} I(T/T{sub F}) 的形式给出——通用碰撞率 {gamma}=k{sub B}T{sub F}/(6{pi}({Dirac_h}/2{pi})) 与温度 T 与费米温度 T{sub F} 之比的无量纲函数的乘积。我们发现 I 在 T/T{sub F}{approx_equal}0.4 时的峰值为 {approx_equal}4.6，在 T/T{sub F}{1.5 时 I{approx_equal}82 (T/T{sub F}){sup 2}。我们估计了最近强相互作用简并费米原子气体实验的碰撞率。
We derive the elastic collision rate for a harmonically trapped Fermi gas in the extreme unitarity limit where the s-wave scattering cross section is {sigma}(k)=4{pi}/k{sup 2}, with ({Dirac_h}/2{pi})k the relative momentum. The collision rate is given in the form {gamma}={gamma} I(T/T{sub F})--the product of a universal collision rate {gamma}=k{sub B}T{sub F}/(6{pi}({Dirac_h}/2{pi})) and a dimensionless function of the ratio of the temperature T to the Fermi temperature T{sub F}. We find that I has a peak value of {approx_equal}4.6 at T/T{sub F}{approx_equal}0.4, I{approx_equal}82 (T/T{sub F}){sup 2} for T/T{sub F}{ 1.5. We estimate the collision rate for recent experiments on a strongly-interacting degenerate Fermi gas of atoms.