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In a recent paper [Phys. Rev. B {\bf 105}, L180415 (2022)], Ly and Manchonused open source code {\tt TKWANT} for time-dependent computational quantumtransport to predict surprising features in the mature field of current pumpingby magnetization dynamics in spintronics -- in the presence of spin-orbit (SO)coupling, the pumped charge current oscillates at both the frequency $\omega_0$of magnetization precession and high harmonics $N=\omega/\omega_0$, reaching{\em astonishingly high} cutoff \mbox{$N_\mathrm{max} \simeq 1000$} byincreasing the SO coupling. However, results in the paper violate two basictheorems of time-dependent quantum transport: ({\em i}) current response totime-periodic external field {\em must be perfectly periodic} itself in thelong time limit for a two-terminal device because its active region is attachedto two semi-infinite leads bringing continuous energy spectrum; and ({\em ii})no DC component of charge current is allowed in the left-right symmetrictwo-terminal devices, or in asymmetric devices its value cannot be changed bysimply increasing the SO coupling. We illustrate these two theorems by usingcompletely different calculations applied to one-dimensional two-terminaldevices with either ferromagnetic (for which the device is left-rightsymmetric) and antiferromagnetic (for the device is left-right asymmetric)active region hosting the Rashba SO coupling. We conclude that harmonics inpumped current in the presence of SO coupling do exist, but their ``ultrahigh''cutoff is an artifact of either ``bugs'' or inadequate algorithms selectedwithin {\tt TKWANT}. Finally, we suggest strategies for {\em validating}time-dependent quantum transport codes, or selection of algorithms by a userwithin putatively validated (by developers) code, prior to deploying them toproduce research papers.

Comment on "Spin-orbit coupling induced ultrahigh-harmonic generation  from magnetic dynamics" with prescriptions on how to validate scientific  software for computational quantum transport