Entanglement, combinatorics and finite-size effects in spin-chains

Abstract

We carry out a systematic study of the exact block entanglement in XXZ spin-chain at Delta=-1/2. We present, the first analytic expressions for reduced density matrices of n spins in a chain of length L (for n<=6 and arbitrary but odd L) of a truly interacting model. The entanglement entropy, the moments of the reduced density matrix, and its spectrum are then easily derived. We explicitely construct the "entanglement Hamiltonian" as the logarithm of this matrix. Exploiting the degeneracy of the ground-state, we find the scaling behavior of entanglement of the zero-temperature mixed state.

5 pages, 4 figures, one mathematica file attached

References in corpus (8)

• Entanglement Spectrum as a Generalization of Entanglement Entropy: Identification of Topological Order in Non-Abelian Fractional Quantum Hall Effect States
• Matrix product states represent ground states faithfully
• Entropy scaling and simulability by Matrix Product States
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• Scaling of entanglement support for Matrix Product States
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Cited by in corpus (1)

• Mutual Information and Boson Radius in c=1 Critical Systems in One Dimension