Entanglement acts as a fundamental resource for many applications in quantum communication. We propose and theoretically analyze methods for preparing and detecting entanglement between the spins of electrons in a mesoscopic environment. The entanglement production mechanism which we present is based on two quantum dots coupled to a superconductor from which paired electrons are injected via Andreev tunneling. The spin-correlated electrons can then hop from the quantum dots into normal leads. For detection we propose to measure the shot noise which is produced by the entangled electrons after they have passed a beam splitter. The enhancement of the noise by a factor of two turns out to be a unique signature for the spin singlet, a maximally entangled state. In a different setting, the entangled ground state in two tunnel-coupled quantum dots is detected via the Aharonov–Bohm oscillations in the co-tunneling current.

PT Journal Article
TI Spin-entangled electrons in mesoscopic systems
AU Burkard G
FAU Burkard G
AU Sukhorukov E V
FAU Sukhorukov EV
AU Recher P
FAU Recher P
AU Loss D
FAU Loss D
DP 10 Sup, 2001
TA Phys. Usp.
VI 44
IP 13
PG 126-131
RX 10.1070/1063-7869/44/10S/S28
URL https://ufn.ru/en/articles/2001/13/ab/
SO Phys. Usp. 2001 Sup 10;44(13):126-131