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Ground-state magnetization curve of a generalized spin-1/2 ladder

Takashi Tonegawa·Takeshi Nishida·Makoto Kaburagi
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Abstract

Employing a method of exact diagonalization for finite-size systems, we investigate the magnetization curve in the ground state of an antiferromagnetic spin-1/2 ladder with additional exchange interactions on diagonal bonds, which is equivalent to an antiferromagnetic spin-1/2 chain with bond-alternating nearest-neighbor and uniform next-nearest-neighbor interactions. It is found that a half-plateau appears in the magnetization curve in a certain range of the interaction constants. This result is discussed in connection with the necessary condition for the appearance of the plateau, recently given by Oshikawa et al.

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Takashi Tonegawa, Takeshi Nishida, Makoto Kaburagi. 1997-12-26. Ground-state magnetization curve of a generalized spin-1/2 ladder. https://doi.org/10.1016/s0921-4526(97)00937-x

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