Cu nuclear quadrupole resonance study of the spin-Peierls compound Cu1-xMgxGeO3: A possibility of precursory dimerization | |
Article | |
关键词: UNIFORM-ANTIFERROMAGNETIC PHASES; LONG-RANGE ORDER; SI-DOPED CUGEO3; NEUTRON-SCATTERING; ELECTRONIC-STATE; CU-63,CU-65 NMR; SYSTEM CUGEO3; LATTICE RELAXATION; SINGLE-CRYSTALS; SOLITON LATTICE; | |
DOI : 10.1103/PhysRevB.65.100406 | |
来源: SCIE |
【 摘 要 】
We report on a zero-field Cu-63 nuclear quadrupole resonance (NQR) study of nonmagnetic Mg impurity substituted Cu1-xMgxGeO3 (single crystals; the spin-Peierls transition temperature T(sp)similar to14, 13.5, and 11 K for x=0, 0.0043, and 0.020) in a temperature range from 4.2 to 250 K. We found that below T*similar to77 K, Cu NQR spectra are broadened and nonexponential Cu nuclear spin-lattice relaxation increases for undoped and more remarkably for Mg-doped samples. The results indicate that random lattice distortion and impurity-induced spins appear below T*, which we associate with a precursor of the spin-Peierls transition. Conventional magnetic critical slowing down does not appear down to 4.2 K below T-sp.
【 授权许可】
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