We theoretically investigate the quantum transports in a junction between asuperconductor and a silicene nanoribbon, under the effect of a magneticexchange field. We find that for a narrow nanoribbon of silicene, remarkablecrossed Andreev reflection (with a fraction $>50\%$) can be induced in theenergy window of the elastic cotunneling, by destroying some symmetries of thesystem. Since the energy responses of electrons to the exchange field areopposite for opposite spins, these transport channels can be well spinpolarized. Moreover, due to the helicity conservation of the topological edgestates, these three transport channels are spatially separated in threedifferent locations of the device, making them experimentally distinguishable.This crossed Andreev reflection is a nonlocal quantum interference betweenopposite edges through evanescent modes. If two superconducting leads withdifferent phases are connected to two edges of the silicene nanoribbon, thecrossed Andreev reflection can present Josephson type oscillations, with amaximal fraction $\sim 100\%$.
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