Comparison of S=0 and S=1/2 Impurities in Haldane Chain Compound, $Y_{2}BaNi{O}_5$

J. Das, A. V. Mahajan, J. Bobroff +3

We present the effect of Zn (S=0) and Cu (S=1/2) substitution at the Ni site of S=1 Haldane chain compound $Y_{2}BaNi{O}_5$. ${}^{89}$Y NMR allows us to measure the local magnetic su…