Upon progressive refinement of energy resolution, the conventional RIXS instrumentation reaches the limit where the bandwidth of incident photons becomes insufficient to deliver an acceptable photon-count rate. We show that the RIXS spectra as a function of energy loss are essentially invariant to their integration over incident energies within the core-hole lifetime. This fact permits the RIXS instrumentation based on the hv2-concept to utilize incident synchrotron radiation over the whole core-hole lifetime window without any compromise on the energy-loss resolution, thereby breaking the photon-count limit.
@article{arxiv.2008.02053,
title = {hv2-concept breaks the photon-count limit of RIXS instrumentation},
author = {Kejin Zhou and Satoshi Matsuyama and Vladimir N. Strocov},
journal= {arXiv preprint arXiv:2008.02053},
year = {2020}
}