TY  - JOUR
A1  - Biesner, Tobias
A1  - Roh, Seulki
A1  - Razpopov, Aleksandar
A1  - Willwater, Jannis
A1  - Süllow, Stefan
A1  - Li, Ying
A1  - Zoch, Katharina M.
A1  - Medarde, Marisa
A1  - Nuss, Jürgen
A1  - Gorbunov, Denis
A1  - Skourski, Yurii
A1  - Pustogow, Andrej
A1  - Brown, Stuart E.
A1  - Krellner, Cornelius
A1  - Valentí, Roser
A1  - Puphal, Pascal
A1  - Dressel, Martin
T1  - Multi-center magnon excitations open the entire Brillouin zone to terahertz magnetometry of quantum magnets
T2  - Advanced quantum technologies
N2  - Due to the small photon momentum, optical spectroscopy commonly probes magnetic excitations only at the center of the Brillouin zone; however, there are ways to override this restriction. In case of the distorted kagome quantum magnet Y-kapellasite, Y3Cu9(OH)19Cl8, under scrutiny here, the spin (magnon) density of states (SDOS) can be accessed over the entire Brillouin zone through three-center magnon excitations. This mechanism is aided by the three different magnetic sublattices and strong short-range correlations in the distorted kagome lattice. The results of THz time-domain experiments agree remarkably well with linear spin-wave theory (LSWT). Relaxing the conventional zone-center constraint of photons gives a new aspect to probe magnetism in matter.
KW  - kagome lattices
KW  - multi-center magnons
KW  - terahertz magnetometry
KW  - terahertz photons
Y1  - 2022
UR  - http://publikationen.ub.uni-frankfurt.de/frontdoor/index/index/docId/81966
UR  - https://nbn-resolving.org/urn:nbn:de:hebis:30:3-819665
SN  - 2511-9044
VL  - 5
IS  - 6, 2200023
PB  - Wiley-VCH Verlag
CY  - Weinheim
ER  -