  On the efforts of enhancing the spin orbit interaction (SOI) of graphene for
seeking the dissipationless quantum spin Hall devices, unique Kane-Mele type
SOI and high mobility samples are desired. However, common external decoration
often introduces extrinsic Rashba-type SOI and simultaneous impurity
scattering. Here we show, by the EDTA-Dy molecule decorating, the Kane-Mele
type SOI is mimicked with even improved carrier mobility. It is evidenced by
the suppressed weak localization at equal carrier densities and simultaneous
Elliot-Yafet spin relaxation. The extracted spin scattering time is
monotonically dependent on the carrier elastic scattering time, where the
Elliot-Yafet plot gives the interaction strength of 3.3 meV. Improved quantum
Hall plateaus can be even seen after the external operation. This is attributed
to the spin-flexural phonon coupling induced by the enhanced graphene ripples,
as revealed by the in-plane magnetotransport measurement.
