Abstract:
Ptychography is a microscopy technique in which resolution is not limited by any lens. Used in the hard X-ray regime, it allows high-resolution radiography with quantitative phase contrast, which is valuable for 2D microscopy in harsh environments or for high-resolution nanotomography. At the Swiss Light Source, we implemented hard X-ray ptychography for user operation, for which we have developed novel acquisition strategies, instrumentation, and reconstruction algorithms. Our main goal is to provide a tool to non-expert users that can focus on a particular scientific case.
In this presentation, I will first introduce the technique of X-ray ptychography and present its current status at the cSAXS beamline, where we routinely provide nanotomography with a resolution that can be as good as 14 nm in 3D [1], depending on the specimen. I will select some examples that illustrate the successful application of X-ray ptychography to relevant scientific cases, such as the monitoring of 3D structural changes in an oxide fuel cell electrode material at the different stages of a redox cycle [2], or the quantification of mass density in starch grown inside yeast cells [3]. Finally, I will discuss the ongoing and future developments that will allow ptychography to benefit from the expected improvements in brilliance provided by diffraction-limited storage rings.
[1] M. Holler, et al., Nature 543, 402 (2017)
[2] S. De Angelis, et al., J. Power Sources 360, 520 (2017)
[3] B. Pfister, et al., eLife 5, e15552 (2016)