Minimal Entanglement Witness from Electrical Current Correlations.
Despite great efforts, an unambiguous demonstration of entanglement of mobile electrons in solid state conductors is still lacking. Investigating theoretically a generic entangler-detector setup, we here show that a witness of entanglement between two flying electron qubits can be constructed from only two current cross correlation measurements, for any nonzero detector efficiencies and noncollinear polarization vectors. We find that all entangled pure states, but not all mixed ones, can be detected with only two measurements, except the maximally entangled states, which require three. Moreover, detector settings for optimal entanglement witnessing are presented.
Department of Physics, Lund University, Box 118, SE-221 00 Lund, Sweden.
F
F
Brange
Department of Physics, Lund University, Box 118, SE-221 00 Lund, Sweden.
O
O
Malkoc
Department of Physics, Lund University, Box 118, SE-221 00 Lund, Sweden.
P
P
Samuelsson