Lattice vibrations of alpha(')-NaV2O5 in the low-temperature phase: An alternative interpretation to magnetic bound states

Article

关键词: SPIN-PEIERLS COMPOUND;    RAMAN-SCATTERING;    X-RAY;    CHARGE;    NAV2O5;    TRANSITION;    CRYSTAL;    LIGHT;    GAP;    SUPERSTRUCTURE;   

DOI  :  10.1103/PhysRevB.65.144303

来源: SCIE

【 摘 要 】

We report high-resolution polarized infrared studies of the quarter-filled spin ladder compound alpha(')-NaV2O5 as a function of temperature (5 Kless than or equal toTless than or equal to300 K). Numerous new modes were detected below the temperature T-c=34 K of the phase transition into a charge ordered nonmagnetic state accompanied by a lattice dimerization. We analyze the Brillouin-zone (BZ) folding due to lattice dimerization at T-c, and show that some peculiarities of the low-temperature vibrational spectrum come from quadruplets folded from the BZ point (1/2, 1/2, 1/4). We discuss an earlier interpretation of the 70-, 107-, and 133-cm(-1) modes as magnetic bound states, and propose the alternative interpretation of folded phonon modes strongly interacting with charge and spin excitations.

【 授权许可】

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