We are excited to see our work on polarization-resolved second harmonic spectroscopy enabling element-resolved angular anisotropy investigations published. In LiNbO3 we directly resolve the Li ion displacement and its correlated action on the Nb-O bonds. This study constitutes the first observation of polarization-resolved SHG in the extreme ultraviolet (XUV) and we show that dipole-based SHG models used regularly in the optical regime allow predicting the SHG polarization in the in the XUV regime. The findings of this work pave the way for future angle and time-resolved XUV-SHG studies with elemental specificity in condensed matter systems.
This work as performed at the SACLA free-electron laser at Sping8/RIKEN in primary collaboration with UC San Diego, Argonne National Lab, LBNL and U Tokyo.
Our paper was now published in Physical Review Letters:
https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.127.237402