High-resolution imaging of ultracold fermions in microscopically tailored optical potentials

TL;DR

This paper demonstrates high-resolution imaging and tailored optical trapping of ultracold fermions at micrometer scales, enabling precise control and observation of quantum gases for simulating complex many-body systems.

Contribution

It introduces a dual-microscope setup for local imaging and potential shaping of ultracold fermions with sub-micrometer resolution, facilitating advanced quantum simulations.

Findings

Achieved 660 nm imaging resolution of ultracold 6Li atoms.

Created various optical trapping geometries including lattices and ring configurations.

Demonstrated loading and detection of few-atom systems in tailored potentials.

Abstract

We report on the local probing and preparation of an ultracold Fermi gas on the length scale of one micrometer, i.e. of the order of the Fermi wavelength. The essential tool of our experimental setup is a pair of identical, high-resolution microscope objectives. One of the microscope objectives allows local imaging of the trapped Fermi gas of 6Li atoms with a maximum resolution of 660 nm, while the other enables the generation of arbitrary optical dipole potentials on the same length scale. Employing a 2D acousto-optical deflector, we demonstrate the formation of several trapping geometries including a tightly focussed single optical dipole trap, a 4x4-site two-dimensional optical lattice and a 8-site ring lattice configuration. Furthermore, we show the ability to load and detect a small number of atoms in these trapping potentials. A site separation of down to one micrometer in combination with the low mass of 6Li results in tunneling rates which are sufficiently large for the implementation of Hubbard-models with the designed geometries.