5 papers
Observation of tunable single-atom Yu-Shiba-Rusinov states
Artem Odobesko, D. Di Sante, A. Kowalski +5
The coupling of a spin to an underlying substrate is the basis for a plethora of phenomena. In the case of a metallic substrate, Kondo screening of the adatom magnetic moment can o…
Kondo screening in Co adatoms with full Coulomb interaction
Angelo Valli, Marc Philipp Bahlke, Alexander Kowalski +3
Using a numerically exact first-principles many-body approach, we revisit the "prototypical" Kondo case of a cobalt impurity on copper. Even though this is considered a well unders…
Single-Co Kondo effect in atomic Cu wires on Cu(111)
Nicolas Néel, Jörg Kröger, Malte Schüler +4
Linear atomic chains containing a single Kondo atom, Co, and several nonmagnetic atoms, Cu, were assembled atom by atom on Cu(111) with the tip of a scanning tunneling microscope.…
Symmetric Improved Estimators for Continuous-time Quantum Monte Carlo
Josef Kaufmann, Patrik Gunacker, Alexander Kowalski +2
We derive equations of motion for Green's functions of the multi-orbital Anderson impurity model by differentiating symmetrically with respect to all time arguments. The resulting…
State- and superstate-sampling in hybridization-expansion continuous-time quantum Monte Carlo
Alexander Kowalski, Andreas Hausoel, Markus Wallerberger +2
Due to the intrinsic complexity of the quantum many-body problem, quantum Monte Carlo algorithms and their corresponding Monte Carlo configurations can be defined in various ways.…