= Solution
Place the wire \b[parallel to the fast scan axis]. The endpoints are then recorded in a fraction of a line period, rather than tens of seconds apart, minimizing the differential drift accumulated between them.
\Image[/past-exam-of-the-mphil-in-micro-and-nanotechnology-enterprise-course-of-the-university-of-cambridge/2020/paper-1-afm-drift.png]
{title=Acquisition-time separation explains the orientation dependence of nanowire drift}
{source=paper-1-afm-drift.py}
This does not remove drift of the wire's transverse position or apparent width between successive lines. A very thin wire parallel to the fast axis may fall between the discrete slow-axis scan lines, so a smaller scan area or denser sampling can be needed. Tip convolution, pixel resolution and feedback lag remain; trace/retrace comparisons and allowing thermal equilibration are still valuable. Increasing the scan speed indefinitely is limited by the scanner and feedback bandwidth.
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