Femtosecond dynamics of momentum-dependent magnetic excitations from resonant inelastic X-ray scattering in CaCu2O3.
Taking spinon excitations in the quantum antiferromagnet CaCu2O3 as an example, we demonstrate that femtosecond dynamics of magnetic electronic excitations can be probed by direct resonant inelastic x-ray scattering (RIXS). To this end, we isolate the contributions of single and double spin-flip excitations in experimental RIXS spectra, identify the physical mechanisms that cause them, and determine their respective time scales. By comparing theory and experiment, we find that double spin flips need a finite amount of time to be generated, rendering them sensitive to the core-hole lifetime, whereas single spin flips are, to a very good approximation, independent of it. This shows that RIXS can grant access to time-domain dynamics of excitations and illustrates how RIXS experiments can distinguish between excitations in correlated electron systems based on their different time dependence.
Leibniz Institute for Solid State and Materials Research IFW Dresden, 01069 Dresden, Germany and Research Department Synchrotron Radiation and Nanotechnology, Paul Scherrer Institut, CH-5232 Villigen PSI, Switzerland.
Valentina
V
Bisogni
Leibniz Institute for Solid State and Materials Research IFW Dresden, 01069 Dresden, Germany.
Stefanos
S
Kourtis
Research Department Synchrotron Radiation and Nanotechnology, Paul Scherrer Institut, CH-5232 Villigen PSI, Switzerland and Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, 14195 Berlin, Germany.
Claude
C
Monney
Research Department Synchrotron Radiation and Nanotechnology, Paul Scherrer Institut, CH-5232 Villigen PSI, Switzerland.
Kejin
K
Zhou
Leibniz Institute for Solid State and Materials Research IFW Dresden, 01069 Dresden, Germany.
Roberto
R
Kraus
Leibniz Institute for Solid State and Materials Research IFW Dresden, 01069 Dresden, Germany.
Chinnathambi
C
Sekar
Research Department Synchrotron Radiation and Nanotechnology, Paul Scherrer Institut, CH-5232 Villigen PSI, Switzerland.
Vladimir
V
Strocov
Leibniz Institute for Solid State and Materials Research IFW Dresden, 01069 Dresden, Germany and Department of Physics, Technical University Dresden, D-1062 Dresden, Germany.
Bernd
B
Büchner
Leibniz Institute for Solid State and Materials Research IFW Dresden, 01069 Dresden, Germany and Department of Physics, Technical University Dresden, D-1062 Dresden, Germany.
Jeroen
J
van den Brink
CNR/SPIN, CNISM, and Dipartimento di Fisica, Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133 Milano, Italy.
Lucio
L
Braicovich
Research Department Synchrotron Radiation and Nanotechnology, Paul Scherrer Institut, CH-5232 Villigen PSI, Switzerland.
Thorsten
T
Schmitt
Leibniz Institute for Solid State and Materials Research IFW Dresden, 01069 Dresden, Germany.
Maria
M
Daghofer
Leibniz Institute for Solid State and Materials Research IFW Dresden, 01069 Dresden, Germany.
Jochen
J
Geck