Figure 1

Schematic of sample rotation geometry in vector tomography. An X-ray beamline with left- or right-circular polarization is focused onto a sample, which can be rotated around the X axis (green arrow), termed the in-place rotation. At each in-plane rotation angle, a tilt series is acquired by rotating the sample around the X axis (red arrow). At each tilt angle, the focused beam scans across the sample and two sets of diffraction patterns with left- and right-circular polarization are collected by a charge-coupled device (CCD) detector.