UNIVERSALITY OF SHOT-NOISE IN MULTITERMINAL DIFFUSIVE CONDUCTORS

We prove the universality of shot noise in multiterminal diffusive con ductors of arbitrary shape and dimension for purely elastic scattering as well as for hot electrons. Using a Boltzmann-Langevin approach we reduce the calculation of shot-noise correlators to the solution of a diffusion equation. We show that shot noise in multiterminal conductor s is a nonlocal quantity and that exchange effects can occur without q uantum phase coherence even at zero electron temperature. Concrete num bers for shot noise are given that can be tested experimentally.