Seminář ÚFKL: Krzysztof Wohlfeld
4. května 2022
Semináře se konají v posluchárně F2 v budově Fyziky.
Ústav fyziky kondenzovaných látek vás zve na přednášku
Krzysztof Wohlfeld (Institute of Theoretical Physics, Faculty of Physics, University of Warsaw) – the INNOLEC project guest:
Understanding the complex states of quantum matter with resonant inelastic x-ray scattering
Recently resonant inelastic x-ray scattering (RIXS) has positioned itself as one of the main spectroscopic techniques that is used to understand the complex states of quantum matter . In this talk I will give a brief overview of the RIXS technique and describe the experiments which have contributed to such a huge success of RIXS.
In the first part, I will concentrate on the experimental observation of an orbiton — a collective excitation of a solid which carries solely an orbital quantum number — and the concomitant separation of the spin and orbital degrees of freedom of an electron in the quasi-one-dimensional copper oxides . Next, in the second part of the talk, I will discuss how RIXS has observed the collective magnetic excitations in the (doped) copper oxides  and how one can understand this phenomenon . I will end the talk by explaining whether this surprising finding could influence the theories of high-temperature superconductivity in these compounds.
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 C. J. Jia et al, Nature Communications 5, 3314 (2014); E. Paerschke et al., Physical Review B 99, 205102 (2019).