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arXiv · 2112.14311

Finite and High-temperature series expansion via many-body perturbation theory

Mohamed Amine Tag·Abid Boudiar·Mohamed El-Hadi Mansour·Abdelkader Hafdallah·Chafia Bendjeroudib
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Abstract

We present a new algorithm to evaluate the grand potential at finite and high-temperature series expansion via many-body perturbation theory. This algorithm allows us to formulate each order as a divided difference. Further, we apply this algorithm to the Heisenberg spin-1/2 XXZ chain. We obtain all coefficients of the high-temperature expansion of the free energy and susceptibility per site of this model up to sixth order.

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Mohamed Amine Tag, Abid Boudiar, Mohamed El-Hadi Mansour, Abdelkader Hafdallah, Chafia Bendjeroudib. 2021-12-28. Finite and High-temperature series expansion via many-body perturbation theory. https://arxiv.org/abs/2112.14311

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