Crossed Andreev reflection in multiterminal structures in the diffusive
regime is addressed within the quasiclassical Keldysh-Usadel formalism. The
elastic cotunneling and crossed Andreev reflection of quasiparticles give
nonlocal currents and voltages (depending on the actual biasing of the devices)
by virtue of the induced proximity effect in the normal metal electrodes. The
magnitude of the nonlocal processes is found to scale with the square of the
barrier transparency and to decay exponentially with interface spacing.
Nonlocal cotunneling and crossed Andreev conductances are found to contribute
equally to the nonlocal current, which is of relevance to the use of normal
metal-superconducting heterostructures as sources of entanglement