Harvard-MIT Center for Ultracold Atoms, Cambridge, Massachusetts 02138, USA.
Phys Rev Lett. 2011 Jul 8;107(2):023204. doi: 10.1103/PhysRevLett.107.023204.
We use accurate ab initio and quantum scattering calculations to demonstrate that the maximum ³He spin polarization that can be achieved in spin-exchange collisions with potassium (³⁹K) and silver (¹⁰⁷Ag) atoms is limited by the anisotropic hyperfine interaction. We find that spin exchange in Ag-He collisions occurs much faster than in K-He collisions over a wide range of temperatures (10-600 K). Our analysis indicates that measurements of trap loss rates of ²S atoms in the presence of cold ³He gas may be used to probe anisotropic spin-dependent interactions in atom-He collisions.
我们使用精确的从头算和量子散射计算来证明，与钾（³⁹K）和银（¹⁰⁷Ag）原子的自旋交换碰撞中所能达到的最大³He 自旋极化度受到各向异性超精细相互作用的限制。我们发现，在很宽的温度范围内（10-600 K），Ag-He 碰撞中的自旋交换比 K-He 碰撞快得多。我们的分析表明，在存在冷 ³He 气体的情况下测量 ²S 原子的陷阱损耗率可以用于探测原子-He 碰撞中的各向异性自旋相关相互作用。
