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arXiv · 1807.04033

Tensor-network approach to compute genuine multisite entanglement in infinite quantum spin chains

Sudipto Singha Roy·Himadri Shekhar Dhar·Aditi Sen De·Ujjwal Sen
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Abstract

We devise a method based on the tensor-network formalism to calculate genuine multisite entanglement in ground states of infinite spin chains containing spin-1/2 or spin-1 quantum particles. The ground state is obtained by employing an infinite time-evolving block decimation method acting upon an initial matrix product state for the infinite spin system. We explicitly show how such infinite matrix product states with translational invariance provide a natural framework to derive the generalized geometric measure, a computable measure of genuine multisite entanglement, in the thermodynamic limit of quantum many-body systems with both spin-1/2 and higher-spin particles.

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Sudipto Singha Roy, Himadri Shekhar Dhar, Aditi Sen De, Ujjwal Sen. 2018-07-11. Tensor-network approach to compute genuine multisite entanglement in infinite quantum spin chains. https://doi.org/10.1103/physreva.99.062305

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