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arXiv · 2011.02625

Matrix Product Wave Function of the Ground State and Elementary Excitation in the Spin-1/2 Chain

Jintae Kim·Minsoo Kim·Pramod Padmanabhan·Jung Hoon Han·Hyun-Yong Lee
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Abstract

We present a variational matrix product state (vMPS) for the ground state of the spin-1/2 Heisenberg model. The MPS effectively organizes the various dimer configurations, in faithful reflection of the resonating valence bond (RVB) picture of the spin liquid, with the energy only 0.024% higher than the exact value given by Bethe ansatz. Building on the ground-state vMPS, the one-spin wave function is constructed in a simple manner with the dispersion that matches well with the exact spectrum. The vMPS scheme is applied to the family of Hamiltonian extrapolating between the Heisenberg model and the Majumdar-Ghosh model.

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Jintae Kim, Minsoo Kim, Pramod Padmanabhan, Jung Hoon Han, Hyun-Yong Lee. 2020-11-05. Matrix Product Wave Function of the Ground State and Elementary Excitation in the Spin-1/2 Chain. https://doi.org/10.1103/physrevb.103.125157

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