O-17 NMR study of the local charge state in the hole-doped Cu2O3 two-leg spin-ladder A(14)Cu(24)O(41) (A(14)=La6Ca8, Sr-14, Sr11Ca3, Sr6Ca8)

Article

关键词: ELECTRIC-FIELD GRADIENTS;    SUSCEPTIBILITY MEASUREMENTS;    CU-OXIDES;    SR14CU24O41;    DYNAMICS;    SR14-XCAXCU24O41;    SPECTROSCOPY;    YBA2CU3O7;    NUCLEI;    CHAINS;   

DOI  :  10.1103/PhysRevB.67.094512

来源: SCIE

【 摘 要 】

NMR measurements of the O-17 nuclear quadrupole interactions (17)nu(Q) show that the charge environment of the S = 1/2 Cu2O3 two-leg spin-ladder layer of hole-doped A(14)Cu(24)O(41) changes dramatically above a certain temperature T*. This temperature T* decreases with additional doping and is correlated with the magnetic crossover from the spin gap regime to the paramagnetic regime. We demonstrate that these changes in (17)nu(Q) are consistent with an increase in the effective hole concentration in the Cu2O3 two-leg ladder above T*. The effective hole concentration increases primarily in the oxygen 2psigma orbitals.

【 授权许可】

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