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arXiv · 1411.2938

The scalar product of XXZ spin chain revisited. Application to the ground state at $Δ=-1/2$

Alexander Garbali
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Abstract

For the scalar product $S_n$ of the XXZ $s=1/2$ spin chain we derive a new determinant expression which is symmetric in the Bethe roots. We consider an application of this formula to the inhomogeneous groundstate of the model with $Δ=-1/2$ with twisted periodic boundary conditions. At this point the ground state eigenvalue $τ_n$ of the transfer matrix is known and has a simple form that does not contain the Bethe roots. We use the knowledge of $τ_n(μ)$ to obtain a closed expression for the scalar product. The result is written in terms of Schur functions. The computations of the normalization of the ground state and the expectation value of $σ^z$ are also presented.

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Alexander Garbali. 2014-11-11. The scalar product of XXZ spin chain revisited. Application to the ground state at $Δ=-1/2$. https://arxiv.org/abs/1411.2938

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