Moal S, Portier M, Kim J, Dugué J, Rapol U D, Leduc M, Cohen-Tannoudji C
Ecole Normale Supérieure and Collège de France, Laboratoire Kastler Brossel, 24 rue Lhomond, 75231 Paris Cedex 05, France.
Phys Rev Lett. 2006 Jan 20;96(2):023203. doi: 10.1103/PhysRevLett.96.023203.
We present a new measurement of the s-wave scattering length a of spin-polarized helium atoms in the 2(3)S1 metastable state. Using two-photon photoassociation spectroscopy and dark resonances, we measure the energy E(nu)=14= -91.35+/- 0.06 MHz of the least-bound state nu = 14 in the interaction potential of the two atoms. We deduce a value of a=7.512+/-0.005 nm, which is at least 100 times more precise than the best previous determinations and is in disagreement with some of them. This experiment also demonstrates the possibility to create exotic molecules binding two metastable atoms with a lifetime of the order of 1 micros.
我们展示了对处于2(3)S1亚稳态的自旋极化氦原子的s波散射长度a的新测量。利用双光子光缔合光谱和暗共振，我们测量了两个原子相互作用势中最束缚态ν = 14的能量E(ν)=14 = -91.35±0.06 MHz。我们推导出a = 7.512±0.005 nm的值，该值比之前最好的测量结果至少精确100倍，并且与其中一些结果不一致。该实验还证明了有可能创造出结合两个亚稳态原子的奇异分子，其寿命约为1微秒。
