Magnetic ground state of the pyrochlore oxide Y2Nb2O7

Article

关键词: FRUSTRATED HEISENBERG-ANTIFERROMAGNET;    REDUCED NIOBATES CALNNB(2)O(7);    SPIN LIQUID;    INSULATOR;    FLUCTUATIONS;    TRANSITION;    LATTICE;    PHASE;    METAL;    ORDER;   

DOI  :  10.1103/PhysRevB.67.054410

来源: SCIE

【 摘 要 】

We report dc magnetization and specific heat of a series of insulating pyrochlore oxides Y2Nb2-xTixO7. Although the end member Y2Nb2O7 contains magnetic tetravalent Nb ions (4d(1), S=1/2), it does not exhibit any sign of magnetic ordering at least between 0.35 and 800 K. In addition, it exhibits Curie-Weiss behavior originating from spins S=1/2 on less than 0.3% of the Nb sites; the remaining spins of Nb ions apparently disappear. With the substitution of nonmagnetic Ti ions, this magnetic component increases only up to 4.7% of the B sites, with Nb and Ti combined. These results are ascribable to a strongly correlated spinless state, which is a specific character derived from a band structure of d-electron pyrochlore oxides.

【 授权许可】

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