A Monte Carlo ray-tracing simulation of coherent X-ray diffractive imaging

Area of Science:

• Optics and Photonics
• Computational Physics
• Materials Science

Background:

• Coherent diffractive imaging (CDI) typically relies on thin sample approximations and Fresnel or Fraunhofer propagators for simulation.
• Existing wave-based or hybrid X-ray simulators often employ these standard wavefront propagation methods.

Purpose of the Study:

• To investigate the applicability and effectiveness of an alternative simulation approach for CDI using ray tracing of Huygens wavelets.
• To evaluate the potential and limitations of this ray-tracing-based method for simulating complex CDI scenarios.

Main Methods:

• Simulating diffraction patterns using ray tracing of Huygens wavelets.
• Validating the method by accurately predicting diffraction fringes from a grating-like source.
• Testing the approach with a ptychography dataset from an experiment with realistic parameters.

Main Results:

• The ray tracing of Huygens wavelets accurately predicts diffraction fringes for grating-like sources.
• Diffraction patterns from realistic ptychography data were sufficiently sampled for phase retrieval.
• The method demonstrates potential for simulating non-standard or imperfect CDI configurations.

Conclusions:

• Ray tracing of Huygens wavelets is a viable alternative for simulating coherent diffractive imaging experiments.
• This approach offers high flexibility for exploring a large parameter space, despite significant computational demands.
• It provides a valuable tool for studying complex CDI setups lacking established theoretical models.