Phase Diagram of the Triangular t-J Model with Multiple Spin Exchange in the Doped-Mott Region

Yuki Fuseya; Masao Ogata

doi:10.1143/jpsj.78.013601

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arXiv · 0804.4329

Phase Diagram of the Triangular t-J Model with Multiple Spin Exchange in the Doped-Mott Region

Yuki Fuseya·Masao Ogata

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Abstract

We study the triangular $t$-$J$ model with multiple spin exchange interactions using exact diagonalization of small clusters, as a model of monolayer liquid $^3$He. A phase where the energy spectrum suggest the behaviors of spin-charge separation is realized in the doped-Mott region due to the competition between ferromagnetic two-spin and antiferromagnetic four-spin exchange interactions. This behavior gives an interpretation of the double peaked heat capacity recently observed in monolayer liquid $^3$He adsorbed on a graphite.

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Yuki Fuseya, Masao Ogata. 2008-11-19. Phase Diagram of the Triangular t-J Model with Multiple Spin Exchange in the Doped-Mott Region. https://doi.org/10.1143/jpsj.78.013601

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