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arXiv · 1003.0909

Spin Filtering and Entanglement Swapping through Coherent Evolution of a Single Quantum Dot

Jose Garcia Coello·Abolfazl Bayat·Sougato Bose·John H. Jefferson·Charles E. Creffield
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Abstract

We exploit the non-dissipative dynamics of a pair of electrons in a large square quantum dot to perform singlet-triplet spin measurement through a single charge detection and show how this may be used for entanglement swapping and teleportation. The method is also used to generate the AKLT ground state, a further resource for quantum computation. We justify, and derive analytic results for, an effective charge-spin Hamiltonian which is valid over a wide range of parameters and agrees well with exact numerical results of a realistic effective-mass model. Our analysis also indicates that the method is robust to choice of dot-size and initialization errors, as well as decoherence introduced by the hyperfine interaction.

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Jose Garcia Coello, Abolfazl Bayat, Sougato Bose, John H. Jefferson, Charles E. Creffield. 2010-08-18. Spin Filtering and Entanglement Swapping through Coherent Evolution of a Single Quantum Dot. https://doi.org/10.1103/physrevlett.105.080502%2010.1103%2Fphysrevlett.105.080502%2010.1103%2Fphysrevlett.105.080502

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