title: Single-shot correlations and two-qubit gate of solid-state spins.
abstract: Measurement of coupled quantum systems plays a central role in quantum information processing. We have realized independent single-shot read-out of two electron spins in a double quantum dot. The read-out method is all-electrical, cross-talk between the two measurements is negligible, and read-out fidelities are ~86% on average. This allows us to directly probe the anticorrelations between two spins prepared in a singlet state and to demonstrate the operation of the two-qubit exchange gate on a complete set of basis states. The results provide a possible route to the realization and efficient characterization of multiqubit quantum circuits based on single quantum dot spins.
authors.affiliation: Kavli Institute of Nanoscience, Delft University of Technology, Post Office Box 5046, 2600 GA Delft, Netherlands. k.c.nowack@tudelft.nl
authors.forename: K C
authors.initials: KC
authors.lastname: Nowack
authors.forename: M
authors.initials: M
authors.lastname: Shafiei
authors.forename: M
authors.initials: M
authors.lastname: Laforest
authors.forename: G E D K
authors.initials: GE
authors.lastname: Prawiroatmodjo
authors.forename: L R
authors.initials: LR
authors.lastname: Schreiber
authors.forename: C
authors.initials: C
authors.lastname: Reichl
authors.forename: W
authors.initials: W
authors.lastname: Wegscheider
authors.forename: L M K
authors.initials: LM
authors.lastname: Vandersypen