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تسجيل مستخدم جديدCurrent noise generated by spin imbalance in presence of spin relaxation
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We calculate current (shot) noise in a metallic diffusive conductor generated by spin imbalance in the absence of a net electric current. This situation is modeled in an idealized three-terminal setup with two biased ferromagnetic leads (F-leads) and one normal lead (N-lead). Parallel magnetization of the F-leads gives rise in spin-imbalance and finite shot noise at the N-lead. Finite spin relaxation results in an increase of the shot noise, which depends on the ratio of the length of the conductor ($L$) and the spin relaxation length ($l_s$). For $Lgg l_s$ the shot noise increases by a factor of two and coincides with the case of the anti-parallel magnetization of the F-leads.
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