TY  - JOUR
PB  - SciPost Foundation
DO  - 10.21468/SciPostPhys.16.3.081
TI  - Exploring kinetically induced bound states in triangular lattices with ultracold atoms: Spectroscopic approach
PY  - 2024/03/20
UR  - https://www.scipost.org/SciPostPhys.16.3.081
JF  - SciPost Physics
JA  - SciPost Phys.
VL  - 16
IS  - 3
SP  - 081
A1  - Morera Navarro, Ivan
AU  - Weitenberg, Christof
AU  - Sengstock, Klaus
AU  - Demler, Eugene
AB  - Quantum simulations with ultracold fermions in triangular optical lattices have recently emerged as a new platform for studying magnetism in frustrated systems. Experimental realizations of the Fermi Hubbard model revealed striking contrast between magnetism in bipartite and triangular lattices. In bipartite lattices magnetism is strongest at half filling, and doped charge carriers tend to suppress magnetic correlations. In triangular-type lattices for large U/t and t>0, antiferromagnetism (ferromagnetism) gets enhanced by doping away from n=1 with holes (doublons) because kinetic energy of dopants can be lowered through developing magnetic correlations, corresponding to formation of magnetic polarons. Snapshots of many-body states obtained with quantum gas microscopes demonstrated existence of magnetic polarons by revealing the magnetic correlations around dopants at temperatures that considerably exceed superexchange energy scale. In this paper we discuss theoretically that additional insight into properties of magnetic polarons in triangular lattices can be achieved using spectroscopic experiments with ultracold atoms. We consider starting from a spin polarized state with small hole doping and applying a two-photon Raman photoexcitation, which transfers atoms into a different spin state. We show that such magnon injection spectra exhibit a separate peak corresponding to formation of a bound state between a hole and a magnon. This polaron peak is separated from the simple magnon spectrum by energy proportional to single particle tunneling and can be easily resolved with currently available experimental techniques. For some momentum transfer there is an additional peak corresponding to photoexciting a bound state between two holes and a magnon. We point out that in two component Bose mixtures in triangular lattices one can also create dynamical magnetic polarons, with one hole and one magnon forming a repulsive bound state.
ER  -

@Article{10.21468/SciPostPhys.16.3.081,
	title={{Exploring kinetically induced bound states in triangular lattices with ultracold atoms: Spectroscopic approach}},
	author={Ivan Morera Navarro and Christof Weitenberg and Klaus Sengstock and Eugene Demler},
	journal={SciPost Phys.},
	volume={16},
	pages={081},
	year={2024},
	publisher={SciPost},
	doi={10.21468/SciPostPhys.16.3.081},
	url={https://scipost.org/10.21468/SciPostPhys.16.3.081},
}