Magnetic phases of one-dimensional lattices with 2 to 4 fermions per site

J. -P. Nikkarila; M. Koskinen; S. M. Reimann; M. Manninen

doi:10.1088/1367-2630/10/6/063013

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arXiv · 0803.2857

Magnetic phases of one-dimensional lattices with 2 to 4 fermions per site

J. -P. Nikkarila·M. Koskinen·S. M. Reimann·M. Manninen

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Abstract

We study the spectral and magnetic properties of one-dimensional lattices filled with 2 to 4 fermions (with spin 1/2) per lattice site. We use a generalized Hubbard model that takes account all interactions on a lattice site, and solve the many-particle problem by exact diagonalization. We find an intriguing magnetic phase diagram which includes ferromagnetism, spin-one Heisenberg antiferromagnetism, and orbital antiferromagnetism.

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J. -P. Nikkarila, M. Koskinen, S. M. Reimann, M. Manninen. 2008-03-19. Magnetic phases of one-dimensional lattices with 2 to 4 fermions per site. https://doi.org/10.1088/1367-2630%2F10%2F6%2F063013

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