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】
Free