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Effects of substituting rare-earth ion R by non-magnetic impurities in $R_2BaNiO_5$ - theory and numerical DMRG results

T. -K. Ng·Jizhong Lou·Zhao-Bin Su
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Abstract

In this paper we study the effect of substituting R (rare-earth ion) by non-magnetic ions in the spin-1 chain material $R_2BaNiO_5$. Using a strong-coupling expansion and numerical density matrix renormalization group calculations, we show that spin-wave bound states are formed at the impurity site. Experimental consequences of the bound states are pointed out.

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T. -K. Ng, Jizhong Lou, Zhao-Bin Su. 2000-08-04. Effects of substituting rare-earth ion R by non-magnetic impurities in $R_2BaNiO_5$ - theory and numerical DMRG results. https://doi.org/10.1103/physrevb.61.11487

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