Abstract

Ultracold atoms in optical lattices have become a tool to simulate and test fundamental concepts of condensed matter physics, in particular to simulate electrons in solid crystals. Recent experiments with single-site resolution of single atoms at individual lattice sites have resulted in the direct observation of quantum phase transitions, such as the superfluid to Mott insulator transition for bosonic particles [1], and, e.g. single-site addressing [2] and the quantum dynamics of spin-impurities [3]. However, an experimental proof of single-site-resolved detection of correlated phases of ultracold fermions in a lattice is still missing. I will report on our current progress to realise single-site resolved, in-situ imaging and manipulation of strongly correlated fermionic 40K in an optical lattice. Such a system would be an ideal environment to simulate the Fermi-Hubbard Hamiltonian, allowing for the direct observation and characterisation of, e.g., temperature, spin-structure, or entropy distribution of quantum phases such as fermionic Mott insulators, Band insulators or Néel antiferromagnets.

[1] J. F. Sherson, C. Weitenberg, M. Endres, M. Cheneau, I. Bloch, S. Kuhr, Single-atom-resolved fluorescence imaging of an atomic Mott insulator, Nature 467, 68 (2010). [2] C. Weitenberg, M. Endres, J. F. Sherson, M. Cheneau, P. Schauß, T. Fukuhara, I.Bloch, S. Kuhr, Single-spin addressing in an atomic Mott insulator, Nature 471, 319 (2011). [3] T. Fukuhara, A. Kantian, M. Endres, M. Cheneau, P. Schauß, S. Hild, D. Bellem, U. Schollwöck, T. Giamarchi, C. Gross, I. Bloch, S. Kuhr, Quantum dynamics of a single, mobile spin impurity, Nature Physics 9, 235 (2013)