DASAPT

What it calibrates

Default reconstruction parameters are rarely sufficient. APT Calibrator collects methods developed over two decades into one interface.

Image compression factor

ICF (ξ) from crystallographic poles on detector hit maps, using theoretical versus observed inter-pole angles. At least two indexed poles are required.

Calibrate ICF from crystallographic poles

Field factor kf

Iterative radius refinement from lattice-plane spacing, then kf from F = V / (kf R). Complements spatial distribution maps in AP Suite.

Charge ratio

Estimate evaporation field from measured charge-state ratios (Müller / Kingham). The field is then used with tip radius and voltage to obtain kf.

Charge-ratio analysis in APT Calibrator

Pole-figure simulator

Azimuthal equidistant projection, closer to APT geometry than gnomonic EBSD-style indexing. Supports LEAP 5000 XS/XR, TKD/EBSD orientations, and grain misorientation.

Pole-figure simulation in APT Calibrator

Golden-seed reconstruction

Fiducial markers from TEM/STEM used for depth-resolved ICF and kf. Useful when poles are weak, or for multilayers, precipitates, and nanocrystalline specimens.

Dynamic reconstruction with golden seeds

Iso-surface

Concentration or density iso-surfaces on a voxel grid with Gaussian delocalization. Surfaces can be shown from both sides, with cluster size and composition statistics.

Iso-surface analysis in APT Calibrator

Volume map

Map concentration, density, peak ratio, or multiplicity through the reconstructed volume. Several saved maps can be shown together.

Volume map of a reconstructed APT needle
Volume map on a reconstructed needle

Slicing

Move a slice through the reconstructed volume to see the atoms inside the needle.

Slice through a reconstructed APT needle
Slice through a reconstructed needle

Cylinder 1D profile

Place a cylinder ROI on the 3D reconstruction and measure composition along its axis. Requires reconstructed XYZ. Open it from the toolbar in Cluster Analysis or DAS APT.

Cylinder 1D concentration profile
Cylinder 1D profile in APT Calibrator

Multiplicity

Map hit-multiplicity density (singles, doubles, triples, 4+) as a volume in the 3D reconstruction. Requires an EPOS file.

Multiplicity analysis in APT Calibrator

Two ways to use it

Export from AP Suite, calibrate here, then return parameters or a reconstructed volume.

Standard calibration

Build detector hit maps and spatial distribution maps in AP Suite. Index poles and iterate radius in APT Calibrator to obtain ICF and kf, then reapply them in the reconstruction wizard.

Overview of APT Calibrator

Correlative dynamic reconstruction

Export .apt to .epos, place golden seeds on matching TEM/STEM features, and compute depth-dependent ICF and kf. Reconstructions can be written as .pos files back into AP Suite.

Cite the software

If you use APT Calibrator in published work, please cite the paper.

Xinren Chen, Yue Li, Eric Woods, Xuyang Zhou, and Baptiste Gault. APT Calibrator: A Multifunctional C# Software Application for Reconstruction Calibration in Atom Probe Tomography. Microscopy and Microanalysis 31, ozaf092 (2025). https://doi.org/10.1093/mam/ozaf092

@article{Chen2025APTCalibrator,
  author  = {Chen, Xinren and Li, Yue and Woods, Eric and Zhou, Xuyang and Gault, Baptiste},
  title   = {{APT Calibrator}: A Multifunctional {C\#} Software Application for Reconstruction Calibration in Atom Probe Tomography},
  journal = {Microscopy and Microanalysis},
  volume  = {31},
  number  = {5},
  pages   = {ozaf092},
  year    = {2025},
  doi     = {10.1093/mam/ozaf092}
}