Condensed Matter Physics Seminar

The manipulation and detection of individual quantum excitations forms the basis of modern quantum optics experiments. However, most of these experiments have been restricted to systems composed of only a few particles.

In recent years, tremendous experimental progress has been made in probing strongly correlated many-body systems at the level of individual particles. For ultracold quantum gases, this was achieved using single-site- and single-atom-resolved imaging in optical lattices. With this technique, 'snapshots' of a fluctuating many-body system are obtained, where individual excitations are directly visible and, by shining light through the imaging system, are also directly addressable.

I will review these developments and present a few chosen experiments in more detail: The single-site-resolved detection of correlation functions [1], the observation of the quantum dynamics of a mobile spin impurity [2], and the detection of an amplitude 'Higgs' mode [3]. I will conclude with analyzing the current limitations and possible future developments, e.g., the detection of entanglement in quantum many-body systems. Concerning the latter topic, I will present preliminary data indicating the experimental quantification of entanglement generated during single-spin impurity dynamics.

[1] M. Endres et al., Science 334, 200 (2011)
[2] T. Fukuhara et al., Nature Phys. 9, 235 (2013)
[3] M. Endres et al., Nature 487, 454-458 (2012)