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arXiv · 2005.03336

Multi-wavelength coherent diffractive imaging

Erik Malm·Edwin Fohtung·Anders Mikkelsen
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Abstract

Coherent diffractive imaging is a technique that recovers the sample image by numerically inverting its diffraction pattern. We propose a generalization of this method for the inversion of multi-wavelength data. Using this approach, we show that separate reconstructions for each wavelength can be recovered from a single polychromatic diffraction pattern. Limitations on the number of wavelengths is provided by adapting the constraint ratio to the polychromatic situation. The method's performance is demonstrated as a function of the source spectrum, the degree of complexity within the exit wave and the sample geometry using several numerical simulations. Lastly, an example shows the ability to recover element-specific information using two harmonics selected from a high-order harmonic generation source.

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Erik Malm, Edwin Fohtung, Anders Mikkelsen. 2020-05-07. Multi-wavelength coherent diffractive imaging. https://arxiv.org/abs/2005.03336

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