2009/05/01 by A. Ramsak, J. Mravlje, T. Rejec +1
Computer Science · Physics and Astronomy · #Antiparallel (mathematics) #Concurrence #Electron #Isotropy #Physics of Superconductivity and Magnetism #Quantum Information and Cryptography #Quantum and electron transport phenomena #Quantum entanglement #Qubit #Scalar (mathematics) #Spin (aerodynamics) #Spins #cond-mat.mes-hall #cond-mat.str-el
paper · pdf · doi:10.1209/0295-5075/86/40003
published as Europhys. Lett. 86, 40003 (2009)
arxiv created 2009/05/01 · openalex publication_date 2009/05/01 · arxiv updated 2015/05/13 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
Entanglement of spins is analyzed for two electrons extracted from a mixed many-electron state by projecting onto the two-electron subspace. The concurrence formulae are expressed in a compact form for states with a well-defined square of the total spin projection. As an example, the thermal entanglement for a qubit pair with an anisotropic Heisenberg and the Dzyaloshinskii-Moriya interactions in an inhomogeneous magnetic field is given analytically. Remarkably, the concurrence of a pair of electrons with antiparallel spins and in a delocalised orbital state is given by the scalar product of the state with its spin-flipped state and not with the time-reversed state.