Search

A quantitative analysis of the effect of strain on image reconstruction in Bragg coherent X-ray diffraction imaging and ptychography reveals reconstruction artifacts caused by the limited spatial resolution. With the modulus homogenization constraint applied, the reconstruction artifacts are efficiently removed and an Fe–Al alloy sample with strong strain that features π phase steps due to anti-phase domain boundaries is successfully reconstructed., A quantitative analysis of the effect of strain on phase retrieval in Bragg coherent X-ray diffraction imaging is reported. It is shown in reconstruction simulations that the phase maps of objects with strong step-like phase changes are more precisely retrieved than the corresponding modulus values. The simulations suggest that the reconstruction precision for both phase and modulus can be improved by employing a modulus homogenization (MH) constraint. This approach was tested on experimental data from a highly strained Fe–Al crystal which also features antiphase domain boundaries yielding characteristic π phase shifts of the (001) superlattice reflection. The impact of MH is significant and this study outlines a successful method towards imaging of strong phase objects using the next generation of coherent X-ray sources, including X-ray free-electron lasers.