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Doping-dependent magnetization plateaux in p-merized Hubbard chains

D. C. Cabra·A. De Martino·A. Honecker·P. Pujol·P. Simon
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Abstract

We study zero-temperature Hubbard chains with periodically modulated hopping at arbitrary filling n and magnetization m. We show that the magnetization curves have plateaux at certain values of m which depend on the periodicity p and the filling. At commensurate filling n a charge gap opens and then magnetization plateaux correspond to fully gapped situations. However, plateaux also arise in the magnetization curves at fixed n between the commensurate values and then the plateau-value of of m depends continuously on n and can thus also become irrational. In particular for the case of dimerized hopping (p=2) and fixed doping we find that a plateau appears at m=1-n. In this case, there is still a gapless mode on the plateau leading to thermodynamic behavior which is different from a completely gapped situation.

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D. C. Cabra, A. De Martino, A. Honecker, P. Pujol, P. Simon. 2000-03-16. Doping-dependent magnetization plateaux in p-merized Hubbard chains. https://doi.org/10.1016/s0375-9601(00)00210-3

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