Experimental evidence of spin-entanglement between two freely propagating electrons
Dmitry Vasilyev (Institut für Physik)

Theory predicts that electrons emitted from the crystalline surfaces upon impact of spin-polarized low energy electrons can be spin-entangled. The entanglement can be quantified by the von Neumann entropy, which closely related to the spin-polarization of emitted electrons. We have experimentally measured spin-polarization of the electron pairs emitted from Cu (111) surface. The experimental results obtained for different orientation of scattering plane broadly agree with theoretical calculation and they are consistent with spin-entanglement between two electrons freely propagating over macroscopic distance.