Quantum impurities in the two-dimensional spin one-half Heisenberg antiferromagnet.
نویسندگان
چکیده
The study of randomness in low-dimensional quantum antiferromagnets is at the forefront of research in the field of strongly correlated electron systems, yet there have been relatively few experimental model systems. Complementary neutron scattering and numerical experiments demonstrate that the spin-diluted Heisenberg antiferromagnet La2Cu1-z(Zn,Mg)(z)O4 is an excellent model material for square-lattice site percolation in the extreme quantum limit of spin one-half. Measurements of the ordered moment and spin correlations provide important quantitative information for tests of theories for this complex quantum-impurity problem.
منابع مشابه
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1 Department of Physics, Graduate School of Science, Tohoku University, Sendai 980-8578, Japan 2 Institute for Solid State Physics, University of Tokyo, Chiba 277-8581, Japan We study the impurity-induced phase transitions in a quasi-one-dimensional Heisenberg antiferromagnet doped with magnetic spin-1/2 impurities and non-magnetic ones. The impurity-induced transition temperature determined by...
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عنوان ژورنال:
- Science
دوره 295 5560 شماره
صفحات -
تاریخ انتشار 2002