Soft X-ray spectro-ptychography on boron nitride nanotubes, carbon nanotubes and permalloy nanorods

TL;DR

This paper demonstrates soft X-ray spectro-ptychography at energies as low as 180 eV, showcasing its capabilities on nanostructures and discussing optimization, challenges, and radiation dose considerations.

Contribution

It introduces optimized methods for low-energy soft X-ray spectro-ptychography and analyzes associated measurement and reconstruction challenges.

Findings

Successful ptychography at 180 eV energy level

Enhanced spatial resolution and phase spectral information

Evaluation of radiation dose increase with overlapping sampling

Abstract

Spectro-ptychography offers improved spatial resolution and additional phase spectral information relative to that provided by scanning transmission X-ray microscopes (STXM). However, carrying out ptychography at the lower range of soft X-ray energies (e.g., below 200 eV to 600 eV) on samples with weakly scattering signals can be challenging. We present soft X-ray ptychography results at energies as low as 180 eV and illustrate the capabilities with results from permalloy nanorods (Fe 2p), carbon nanotubes (C 1s), and boron nitride bamboo nanostructures (B 1s, N1s). We describe optimization of low energy X-ray spectro-ptychography and discuss important challenges associated with measurement approaches, reconstruction algorithms, and their effects on the reconstructed images. A method for evaluating the increase in radiation dose when using overlapping sampling is presented.