چکیده
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In this study, Rashba coupling induced Aharonov-Casher effect in a graphene based nano ring is investigated theoretically. The graphene based nano ring is considered as a central device connected to semiinfinite graphene nano ribbons. In the presence of the Rashba spin-orbit interaction, two armchair shaped
edge nano ribbons are considered as semi-infinite leads. The non-equilibrium Green’s function approach
is utilized to obtain the quantum transport characteristics of the system. The relaxation and dephasing
mechanisms within the self-consistent Born approximation is scrutinized. The Lopez-Sancho method is
also applied to obtain the self-energy of the leads. We unveil that the non-equilibrium current of the system possesses measurable Aharonov-Casher oscillations with respect to the Rashba coupling strength. In
addition, we have observed the same oscillations in dilute impurity regimes in which amplitude of the
oscillations is shown to be suppressed as a result of the relaxations.
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