Fölling Simon, Widera Artur, Müller Torben, Gerbier Fabrice, Bloch Immanuel
Johannes Gutenberg-Universität, Staudingerweg 7, 55118 Mainz, Germany.
Phys Rev Lett. 2006 Aug 11;97(6):060403. doi: 10.1103/PhysRevLett.97.060403. Epub 2006 Aug 10.
We report on the direct observation of the transition from a compressible superfluid to an incompressible Mott insulator by recording the in-trap density distribution of a Bosonic quantum gas in an optical lattice. Using spatially selective microwave transitions and spin-changing collisions, we are able to locally modify the spin state of the trapped quantum gas and record the spatial distribution of lattice sites with different filling factors. As the system evolves from a superfluid to a Mott insulator, we observe the formation of a distinct shell structure, in good agreement with theory.
我们通过记录光晶格中玻色子量子气体的阱内密度分布，直接观察到了从可压缩超流体到不可压缩莫特绝缘体的转变。利用空间选择性微波跃迁和自旋改变碰撞，我们能够局部改变捕获的量子气体的自旋状态，并记录具有不同填充因子的晶格位点的空间分布。随着系统从超流体演变为莫特绝缘体，我们观察到形成了一种独特的壳层结构，这与理论高度吻合。
