Entanglement of electron spins in superconductors

Abstract

We investigate entanglement of two electron spins forming Cooper pairs in an s-wave superconductor. The two-electron space-spin density matrix is obtained from the BCS ground state using a two-particle Green's function. It is demonstrated that a two spin state is not given by a spin singlet state but by a Werner state. It is found that the entanglement length, within which two spins are entangled, is not the order of the coherence length but the order of the Fermi wave length.

4 pages, 2 eps figures

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Cited by in corpus (17)

• Carbon Nanotubes as Cooper Pair Beam Splitters
• Detecting entanglement with a thermometer
• Energy entanglement in normal metal-superconducting forks
• Entanglement properties of topological color codes
• Entanglement of an impurity and conduction spins in the Kondo model
• Fermionic Entanglement in Superconducting Systems
• Entanglement modes and topological phase transitions in superconductors
• Entanglement spectrum and number fluctuations in the spin-partitioned BCS ground state
• Entanglement signatures of the quantum phase transition induced by a magnetic impurity in a superconductor
• Structure of quantum correlations in momentum space and off diagonal long range order in eta pairing and BCS states
• Divergent beams of nonlocally entangled electrons emitted from hybrid normal-superconducting structures
• Understanding entangled spins in QED
• Aharonov-Bohm and Aharonov-Casher effects for local and nonlocal Cooper pairs
• Quantum Information Aspects on Bulk and Nano Interacting Fermi System: Spin-Space Density Matrix Approach
• Bipartite representations and many-body entanglement of pure states of $N$ indistinguishable particles
• Method of constructing braid group representation and entanglement in a Yang-Baxter sysytem
• Quantum Separability of Thermal Spin One Boson Systems