학술논문
Separation of kinetic rate orders in extreme ultraviolet transient grating spectroscopy.
Document Type
Article
Author
Marroux, Hugo J B; Polishchuk, Serhii; Cannelli, Oliviero; Ingle, Rebecca A; Mancini, Giulia F; Bacellar, Camila; Puppin, Michele; Geneaux, Romain; Knopp, Gregor; Foglia, Laura; Pedersoli, Emanuele; Capotondi, Flavio; Nikolov, Ivaylo Petrov; Bencivenga, Filippo; Mincigrucci, Riccardo; Masciovecchio, Claudio; Chergui, Majed
Source
Subject
*SPECTROMETRY
*SPINEL
*ELECTRON-hole recombination
*COBALT oxides
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Language
ISSN
0953-4075
Abstract
We present an extreme ultraviolet (EUV) transient grating (TG) experiment of the spinel Co3O4 compound using tuneable incident energies across the Co M2,3-edge and a 395 nm probe pulse, detecting both the first and the second diffraction orders (SDOs). While the first diffraction order shows a monotonous behavior as a function of time, with a sharp response at t = 0, followed by a weak sub-picosecond component and a nearly constant signal thereafter, the time dependence of SDO varies dramatically with the incident energy as it is tuned across the Co M-edge, with the appearance of a component at t > 1 ps that grows with increasing energy. The results are rationalized in terms of the deviations of the initial grating from sinusoidal to non-sinusoidal, namely a flattening of the grating pattern, that introduces new Fourier components. These deviations are due to higher order, three-body terms in the population relaxation kinetics. The present results highlight the use of the SDO response in EUV TG as a tool to identify higher order terms in the population kinetics. [ABSTRACT FROM AUTHOR]