  In a recent preprint arXiv:2203.15521 G. X. Chan, P. Huang, and X. Wang claim
that triple-quantum dot superexchange in a (1, 0, 1) charge configuration
exhibits a change of sign (going from positive to negative) as a function of
middle dot detuning. Furthermore, their claim is that charge sweet-spots exist
for specific values of the inter-dot detuning. Their analysis is based on the
Hubbard model and something to what they refer to as the full
Configuration-Interaction method. All of this findings were already reported by
M. J. Ran\v{c}i\'{c} and G. Burkard in Ref. Phys. Rev. B 96, 201304(R) (2017)
based on the Hubbard model. No reference to this manuscript was made in Ref.
arXiv:2203.15521. I have asked the authors to urgently modify the pre-print and
position their work with respect to the previously conducted study - which they
rejected to do at the current moment, quoting that pp. it is not their style to
modify preprints before they were accepted. This alongside with a very similar
style of some figures lead me to the conclusion that they are deliberately
misleading the scientific community and trying to adopt other peoples work and
ideas as their own.
