TY  - JOUR
AU  - Kroll, Thomas
AU  - Weninger, Clemens
AU  - Alonso-Mori, Roberto
AU  - Sokaras, Dimosthenis
AU  - Zhu, Diling
AU  - Mercadier, Laurent
AU  - Majety, Vinay P.
AU  - Marinelli, Agostino
AU  - Lutman, Alberto
AU  - Guetg, Marc W.
AU  - Decker, Franz-Josef
AU  - Boutet, Sébastien
AU  - Aquila, Andy
AU  - Koglin, Jason
AU  - Koralek, Jake
AU  - DePonte, Daniel P.
AU  - Kern, Jan
AU  - Fuller, Franklin D.
AU  - Pastor, Ernest
AU  - Fransson, Thomas
AU  - Zhang, Yu
AU  - Yano, Junko
AU  - Yachandra, Vittal K.
AU  - Rohringer, Nina
AU  - Bergmann, Uwe
TI  - Stimulated X-Ray Emission Spectroscopy in Transition Metal Complexes
JO  - Physical review letters
VL  - 120
IS  - 13
SN  - 1079-7114
CY  - College Park, Md.
PB  - APS
M1  - PUBDB-2019-00874
SP  - 133203
PY  - 2018
AB  - We report the observation and analysis of the gain curve of amplified Kα x-ray emission from solutions of Mn(II) and Mn(VII) complexes using an x-ray free electron laser to create the 1s core-hole population inversion. We find spectra at amplification levels extending over 4 orders of magnitude until saturation. We observe bandwidths below the Mn 1s core-hole lifetime broadening in the onset of the stimulated emission. In the exponential amplification regime the resolution corrected spectral width of ∼1.7  eV FWHM is constant over 3 orders of magnitude, pointing to the buildup of transform limited pulses of ∼1  fs duration. Driving the amplification into saturation leads to broadening and a shift of the line. Importantly, the chemical sensitivity of the stimulated x-ray emission to the Mn oxidation state is preserved at power densities of ∼10<sup>20</sup>  W/cm<sup>2</sup> for the incoming x-ray pulses. Differences in signal sensitivity and spectral information compared to conventional (spontaneous) x-ray emission spectroscopy are discussed. Our findings build a baseline for nonlinear x-ray spectroscopy for a wide range of transition metal complexes in inorganic chemistry, catalysis, and materials science. 
LB  - PUB:(DE-HGF)16
C6  - pmid:29694162
UR  - <Go to ISI:>//WOS:000428394800008
DO  - DOI:10.1103/PhysRevLett.120.133203
UR  - https://bib-pubdb1.desy.de/record/419010
ER  -