140 citations · 344 across the 22 of their papers we have counts for
5 papers · 1 filter
Holes and magnetic polarons in a triangular lattice antiferromagnet
Jasper van de Kraats, Kristian K. Nielsen, Georg M. Bruun
The intricate interplay between charge motion and magnetic order in geometrically frustrated lattices is central for the properties of many two-dimensional quantum materials. The t…
Equilibrium and non-equilibrium dynamics of a hole in a bilayer antiferromagnet
Jens H. Nyhegn, Kristian K. Nielsen, Georg M. Bruun
The dynamics of charge carriers in lattices of quantum spins is a long standing and fundamental problem. Recently, a new generation of quantum simulation experiments based on atoms…
Exact nonequilibrium hole dynamics, magnetic polarons and string excitations in antiferromagnetic Bethe lattices
K. Knakkergaard Nielsen
We investigate a rare instance of an exactly solvable nonequilibrium many-body problem. In particular, we derive an exact solution for the nonequilibrium dynamics of an initially l…
Life and death of the Bose polaron
Magnus G. Skou, Kristian Knakkergaard Nielsen, Thomas G. Skov +6
Spectroscopic and interferometric measurements complement each other in extracting the fundamental properties of quantum many-body systems. While spectroscopy provides precise meas…
Nonequilibrium Hole Dynamics in Antiferromagnets: Damped Strings and Polarons
K. Knakkergaard Nielsen, T. Pohl, G. M. Bruun
We develop a nonperturbative theory for hole dynamics in antiferromagnetic spin lattices, as described by the - model. This is achieved by generalizing the selfconsistent Bor…