Imaging via Correlation of X-Ray Fluorescence Photons
F. Trost, Kartik Ayyer, Mauro Prasciolu, Holger Fleckenstein, Miriam Barthelmeß, Oleksandr Yefanov, J. Lukas Dresselhaus, Chufeng Li, S. Bajt, Jérôme Carnis, Tamme Wollweber, Abhishek Mall, Zhou Shen, Yulong Zhuang, Stefan Richter, Sebastian Karl, Sebastian Cardoch, Kajwal Kumar Patra, Johannes Möller, Alexey Zozulya, Roman Shayduk, Wei Lu, Felix Brauße, Bertram Friedrich, Ulrike Boesenberg, Ilia Petrov, Sergey Tomin, Marc Guetg, Anders Madsen, Nicuşor Tı̂mneanu, Carl Caleman, Ralf Röhlsberger, J. von Zanthier, Henry N. Chapman
Abstract
We demonstrate that x-ray fluorescence emission, which cannot maintain a stationary interference pattern, can be used to obtain images of structures by recording photon-photon correlations in the manner of the stellar intensity interferometry of Hanbury Brown and Twiss. This is achieved utilizing femtosecond-duration pulses of a hard x-ray free-electron laser to generate the emission in exposures comparable to the coherence time of the fluorescence. Iterative phasing of the photon correlation map generated a model-free real-space image of the structure of the emitters. Since fluorescence can dominate coherent scattering, this may enable imaging uncrystallised macromolecules.