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Finite size effects in entangled rings of qubits

T. Meyer·U. V. Poulsen·K. Eckert·M. Lewenstein·D. Bruss
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Abstract

We study translationally invariant rings of qubits with a finite number of sites N, and find the maximal nearest-neighbor entanglement for a fixed z component of the total spin. For small numbers of sites our results are analytical. The use of a linearized version of the concurrence allows us to relate the maximal concurrence to the ground state energy of an XXZ spin model, and to calculate it numerically for N<25. We point out some interesting finite-size effects. Finally, we generalize our results beyond nearest neighbors.

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T. Meyer, U. V. Poulsen, K. Eckert, M. Lewenstein, D. Bruss. 2003-08-14. Finite size effects in entangled rings of qubits. https://arxiv.org/abs/quant-ph/0308082

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