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Y NMR imaging of the staggered magnetization in doped Haldane chain Y(2)BaNi(1-x)Mg(x)O(5)

F. Tedoldi·R. Santachiara·M. Horvatic
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Abstract

We present a static, model-independent, experimental determination of the spin-spin correlation length ξin a quantum spin system. This is achieved in doped Haldane (i.e., S=1 Heisenberg antiferromagnetic) chain Y(2)BaNi(1-x)Mg(x)O(5) by Y NMR imaging of the staggered magnetization induced around the Mg-impurities (i.e., chain boundaries) by magnetic field. The magnitude of this magnetization is found to decay exponentially with ξequal to the theoretical prediction for an infinite S=1 chain, and the staggered magnetic moment at the edge site showing the Curie behavior of an effective S=1/2 spin.

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F. Tedoldi, R. Santachiara, M. Horvatic. 1999-03-10. Y NMR imaging of the staggered magnetization in doped Haldane chain Y(2)BaNi(1-x)Mg(x)O(5). https://doi.org/10.1103/physrevlett.83.412

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