Assembling many-body systems atom by atom: A bottom-up approach

29 06/2015

Monday, 29 Jun. 2015, 17:30 - 19:00

Presenter: Selim Jochim
Host: Thorsten Schumm
Where: ATI, Lecture Hall, Stadionallee 2, 1020 Vienna

During the past years we established a technique to prepare finite samples of ultracold fermions in a tightly focused optical trap with very low entropy. A spin chain with antiferromagnetic order can be formed by adiabatically ramping up the repulsion between the particles.

We are currently expanding our technique to load periodic potentials with similarly low entropies. We have developed a set of tools to achieve that goal. As a starting point we have realized a double well containing two fermionic atoms in a spin-singulett configuration. We can tune on-site interaction, tunneling rate and tilt of this basic building block of the Hubbard model. This double well can also be prepared with two particles per site, where now tunneling and on-site interaction compete.

In a separate effort, we have realized a strongly interacting two-dimensional Fermi gas in the superfluid regime in an optical lattice potential. Driving this system to a Mott insulator state, we would end up in a scaled-up version of the double well containing a pair of atoms in each site. Our vision is to create correlations between the sites when one atom per well is spilled from the trap. Progress on this effort will be reported.