Fano resonance enhances x-ray intensity

Nuclear resonant scattering of x rays is an important method to probe the dynamics and structure of condensed matter. As the bandwidth of a synchrotron-radiation pulse is much broader than the linewidth of Mössbauer isotopes in a target, the resonant fraction of the incident x-ray photons is extremely tiny. This work proposes using magnetic switching to control the interference between the off-resonant background x rays and the resonant scattered signal, for enhancement of the output intensity via Fano resonance. This scheme points toward a bright, flexible x-ray source for precision spectroscopy utilizing modern synchrotrons. This work is published in Phys. Rev. Applied 18, L051001 (2022).