Hannover 2016 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe

Q: Fachverband Quantenoptik und Photonik

Q 61: Quantum Gases: Fermions II

Q 61.6: Vortrag

Freitag, 4. März 2016, 12:15–12:30, e001

Emergence of orthogonality in the Fermi impurity problem — •Andrea Bergschneider, Michael Dehabe, Jan Hendrik Becher, Vincent M. Klinkhamer, Simon Murmann, Gerhard Zürn, and Selim Jochim — Physikalisches Institut der Universität Heidelberg, Im Neuenheimer Feld 226, 69120 Heidelberg, Germany

In quasi-one-dimensional systems, the ground-state wave function of an impurity particle interacting with a Fermi sea is orthogonal to the wave function of the non-interacting system. In this case the squared overlap between the interacting and the non-interacting systems, which is defined as the quasiparticle residue, is zero.

Here, we report on measurements of the residue of a single fermionic impurity particle interacting with an increasing number of majority particles. To probe the system, we flip the spin of the impurity particle by driving a radio frequency (RF) transition. In a previous experiment we used RF spectroscopy to measure the interaction energy in this system while increasing the number of majority particles one atom at a time and thereby observed the crossover from few to many-body physics [1]. Now, we measure how the wave function overlap between initial and final states changes both as a function of interaction strength and the number of majority particles. Our goal is to extend these measurements into the crossover region between few and many-body physics by increasing the number of majority particles and thereby observe the emergence of the orthogonality catastrophe.

[1] Wenz et al. Science 342, 457 (2013)