Phase diagram of a frustrated mixed-spin ladder with diagonal exchange bonds

N. B. Ivanov; J. Richter

doi:10.1103/physrevb.69.214420

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Phase diagram of a frustrated mixed-spin ladder with diagonal exchange bonds

N. B. Ivanov·J. Richter

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Abstract

Using exact numerical diagonalization and the conformal field theory approach, we study the effect of magnetic frustrations due to diagonal exchange bonds in a system of two coupled mixed-spin $(1,{1/2})$ Heisenberg chains. It is established that relatively moderate frustrations are able to destroy the ferrimagnetic state and to stabilize the critical spin-liquid phase typical for half-integer-spin antiferromagnetic Heisenberg chains. Both phases are separated by a narrow but finite region occupied by a critical partially-polarized ferromagnetic phase.

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N. B. Ivanov, J. Richter. 2004-04-29. Phase diagram of a frustrated mixed-spin ladder with diagonal exchange bonds. https://doi.org/10.1103/physrevb.69.214420

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