Griesmaier Axel, Werner Jörg, Hensler Sven, Stuhler Jürgen, Pfau Tilman
5. Physikalisches Institut, Universität Stuttgart, 70550 Stuttgart, Germany.
Phys Rev Lett. 2005 Apr 29;94(16):160401. doi: 10.1103/PhysRevLett.94.160401.
We report on the generation of a Bose-Einstein condensate in a gas of chromium atoms, which have an exceptionally large magnetic dipole moment and therefore underlie anisotropic long-range interactions. The preparation of the chromium condensate requires novel cooling strategies that are adapted to its special electronic and magnetic properties. The final step to reach quantum degeneracy is forced evaporative cooling of 52Cr atoms within a crossed optical dipole trap. At a critical temperature of T(c) approximately 700 nK, we observe Bose-Einstein condensation by the appearance of a two-component velocity distribution. We are able to produce almost pure condensates with more than 50,000 condensed 52Cr atoms.
我们报道了在铬原子气体中实现玻色-爱因斯坦凝聚，铬原子具有异常大的磁偶极矩，因此是各向异性长程相互作用的基础。制备铬凝聚体需要适应其特殊电子和磁性特性的新型冷却策略。达到量子简并的最后一步是在交叉光偶极阱内对52Cr原子进行强迫蒸发冷却。在约700 nK的临界温度T(c)下，我们通过双组分速度分布的出现观测到玻色-爱因斯坦凝聚。我们能够产生含有超过50,000个凝聚52Cr原子的几乎纯净的凝聚体。
