Direct Exchange versus the indirect Exchange of the t-J Hamiltonian in HTSC Cuprates

Moshe Dayan

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arXiv · 1502.05353

Direct Exchange versus the indirect Exchange of the t-J Hamiltonian in HTSC Cuprates

Moshe Dayan

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Abstract

The direct exchange integral and the transfer integral are calculated for the anti-bonding wave-function of the HTSC cuprates. The direct exchange integral yields a value three times larger than the indirect exchange of the t-J Hamiltonian. It also predicts positive exchange energy for neighboring parallel spins, contrary to the prediction of zero energy by the t-J Hamiltonian. A modified t-J Hamiltonian is proposed, and the implications of the results are discussed.

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Moshe Dayan. 2015-02-17. Direct Exchange versus the indirect Exchange of the t-J Hamiltonian in HTSC Cuprates. https://arxiv.org/abs/1502.05353

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