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arXiv · 1505.06083

Diverging scaling with converging multisite entanglement in odd and even quantum Heisenberg ladders

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

We investigate finite-size scaling of genuine multisite entanglement in the ground state of quantum spin-1/2 Heisenberg ladders. We obtain the ground states of odd- and even-legged Heisenberg ladder Hamiltonians and compute genuine multisite entanglement, the generalized geometric measure (GGM), which shows that for even rungs, GGM increases for odd-legged ladder while it decreases for even ones. Interestingly, the ground state obtained by short-range dimer coverings, under the resonating valence bond (RVB) ansatz, encapsulates the qualitative features of GGM for both the ladders. We find that while the GGMs for higher legged odd- and even-ladders converge to a single value in the asymptotic limit of a large number of rungs, the finite-size scaling exponents of the same tend to diverge. The scaling exponent of GGM obtained by employing density matrix recursion method is therefore a reliable quantity in distinguishing the odd-even dichotomy in Heisenberg ladders, even when the corresponding multisite entanglements merge.

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Sudipto Singha Roy, Himadri Shekhar Dhar, Debraj Rakshit, Aditi Sen De, Ujjwal Sen. 2016-02-18. Diverging scaling with converging multisite entanglement in odd and even quantum Heisenberg ladders. https://arxiv.org/abs/1505.06083

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