Towards picometer resolution at femtosecond scale - novel research infrastructure horizonts

Latvijas Universitātes Cietvielu fizikas institūta, Doktorantūras skolas „Funkcionālie materiāli un nanotehnoloģijas” zinātniskais seminārs uzstājās Prof. Dr. Alexander V. Soldatov (Director, The Smart Materials Research Institute Southern Federal University of Russia).

Fine details in the nanoscale local atomic, electronic, and magnetic structures determine most of the properties of advanced functional materials without long- range order in the atoms positions. To gain deeper insight into the nature of the “structure-property” relation, one has to use several advanced experimental methods for nanocharacterization, including modern approaches making also use of the opportunities at large-scale research facilities, like synchrotron-radiation facilities and x-ray free electron lasers.

The status of cutting-edge spectroscopies for the determination of parameters of the 3D local atomic, electronic, and magnetic structure is presented. One of the methods for extracting the 3D structure parameters is given by an advanced quantitative analysis of X-ray absorption near-edge structure (XANES) spectra that has been developed at the Smart Materials Research Institute of Southern Federal University (http://nano.sfedu). The possibility to extract information on bond angles and bond lengths (with an accuracy up to 1 pm) is demonstrated. This opens new perspectives for XANES as a 3D local-structure probe for any type of material without long-range order in the atomic positions.

Even more possibilities for applications are given by in-situ and in-operando techniques that open up a road for the study of a material not only in its static state, but also during processes involving the material. Time-dependent x-ray spectroscopic methods make it nowadays possible to obtain time resolutions in the picosecond and femtosecond range.